My Grand Am died. I need help

KillNThrill24

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Didn't know what to title it but my Grand Am just died for the third time in 2 weeks. This time I'm not sure WHAT'S wrong with it. Started driving home from work after another 10hr day and the second I turned the car on it was sitting at 1200rpm. Strange, I thought. But nonetheless I kept driving. Thought maybe it was cold so it was idling high (although this will be the 5th winter I've driven this car, and never had it idled that high before). Slowed down as I turned out of my parking lot to turn onto the street to start my trip home. Noticed a strange bogging... Hit the gas and it almost felt like the brakes were hanging the way it was accelerating (again I've had this car 5yrs I know exactly how it should accelerate, even cold). Thought again to myself, that I should feel the wheel's when I get out to see if they were abnormally hot. I had my e-brake hang up on my Mustang and the wheel was on freaking fire, needless to say half of my e-brake is disconnected at the moment. Well right after I thought that I went ahead and let off the gas to see how fast the speed dropped. O it dropped alright, but what caught my eye was the RPM gauge which dropped down to 4-500rpm. I thought, again, shit I hope I can limp this fukker home.

Sure enough as I approached the stop sign I had to brake with my left foot, put the car in neutral and keep pumping the gas with my right foot. I tried to keep constant pressure on the gas but that proved to be too much of a challenge when braking, the RPM's would drop fast as I approached stop and I would have to stomp the gas to get it going again, so I just pumped it instead. Made that turn, barely, and continued on my way. Approached the next light, which was red, and it died. Couldn't get my feet moving fast enough as I'm not used to braking with my left foot and it just died. Took 5 attempts to get it started. The odd part is, it never cranked. The key did nothing at all. Almost as if the starter was dead. Well I replaced the starter last year, it's fine. Finally I got it started again and when the key finally cranked the motor it started up right away, ruling out starter issues.

So by a miracle I limped it all the way home the remaining 15mi and somehow made every single light. It only died once in the process and again it was because I wasn't used to braking with my left foot. Started getting the hang of it and made it home. Had I hit a red light I would have surely been screwed, I rolled the 3 stop signs big time.

Got it partway up my drive way and put it in park, expecting it to die. WELL it didn't. Bastard sat there pulsing for 10min while I moved my Camaro out into the grass next to the driveway. Got back in it, put it in drive and it died. Couldn't get it started again. Started pushin. Pushing uphill sucks, so I got it moved 3 inches lol. Mom tried starting it since she was in it and baaaaaarely got it started and had the pedal to the floor and got it up the driveway. It then died, and now there's a funky smell behind it.

My guess would unfortunately be a fuel pump. What do you guys think? I thought initially alternator, but I don't know. It's gotta be one or the other, or both. And for the record I got underneath the back of it and clearly heard the pump running. But that doesn't mean running well does it? Sorry for the story, but I wanted to include as many details as I could to hopefully help you guys understand what exactly it's doing.
 

chris91

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Yeah you said it smelled funny. Happen to smell of rotten eggs? Could very well be a clogged catalytic convertor.
 
OP
OP
KillNThrill24

KillNThrill24

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Here's what I got guys (always nice to have Auto Enginuity at my fingertips)

P0113 - Intake Air Temperature Circuit High Input
P0401 - Exhaust Gas Recirculation Flow Insufficient Detected
P0442 - Evaporative Emission Control System Leak Detected (Small Leak)
P1404 - Exhaust Gas Recirculation Closed Position Performance OR Exhaust Gas Recirculation Closed Position Performance
P1441 - EVAP Canister Continuous Open Purge Flow OR Evaporative Emission System Flow During Non-Purge
P0300 - Random/Multiple Cylinder Misfire Detected

O boy where do I even begin?
 

Raffaelli

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99% sure its the crank sensor. If not that the ignition module.

When it dies again check for spark and injector pulse.

I know 60degreev6's front to back. Lol
 

CC'S95GT

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PO113- Circuit Description
The Intake Air Temperature (IAT) sensor is a thermistor which measures the temperature of the air entering the engine. The PCM applies 5V through a pull up resistor to the IAT sensor. When the intake air is cold, the sensor resistance is high and the PCM will monitor a high signal voltage on the IAT signal circuit. If the intake air is warm, the sensor resistance is lower causing the PCM to monitor a lower voltage. DTC P0113 will set when the PCM detects an excessively high signal voltage on the intake air temperature sensor signal circuit.

Conditions for Setting the DTC
  • No active ECT sensor or VSS DTC present.
  • Vehicle speed is less than 35 mph.
  • Mass Air Flow is less than 12 gm/s.
  • Engine Coolant Temperature is greater than 60°C (140°F).
  • IAT signal voltage indicates an intake air temperature less than -37°C (-34°F).
  • The above conditions are present for at least 3 minutes.
Action Taken When the DTC Sets

  • The PCM will illuminate the MIL during the second consecutive trip in which the diagnostic test has been run and failed.
  • The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.
Conditions for Clearing the MIL/DTC

  • The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
  • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
  • The DTC can be cleared by using a scan tool.
Diagnostic Aids
Check for the following conditions:

  • Poor connection at PCM. Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
  • Damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, observe the IAT display on the scan tool while moving connectors and wiring harnesses related to the IAT sensor. A change in the IAT display will indicate the location of the fault.
  • The Temperature vs. Resistance table may be used to test the IAT sensor at various temperatures to evaluate the possibility of a shift sensor that may be open above or below a certain temperature. If this is the case, replace the IAT sensor. If the IAT sensor appears to be OK, the fault is intermittent. Refer to Diagnostic Aids above.
 

CC'S95GT

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PO401
Circuit Description
The PCM tests the EGR system during deceleration by momentarily commanding the EGR valve to open while monitoring the Manifold Absolute Pressure (MAP) sensor signal. When the EGR valve is opened, the PCM should see a proportional increase in MAP. If the expected increase in MAP is not seen, the PCM notes the amount of error that was detected and adjusts an internal fail counter towards a fail threshold level. When the fail counter exceeds the fail threshold level, the PCM will set DTC P0401.
The number of test samples required to accomplish this may vary according to the amount of detected flow error.
Normally, the PCM will only allow one EGR flow test sample to be taken during an ignition cycle. To aid in verifying a repair, the PCM allows twelve test samples during the first ignition cycle following a scan tool Clear Info or a battery disconnect. Between nine and twelve samples should be sufficient for the PCM to determine adequate EGR flow and pass the EGR test.

Conditions for Setting the DTC
  • No TP sensor, Vehicle Speed Sensor, injector circuit, Misfire, IAT sensor, MAP sensor, Idle speed, EGR Pintle Position sensor, ECT sensor, CKP sensor, or MAF sensor DTCs set.
  • The AC status does not change.
  • The transaxle range does not change.
  • TP angle is less than 1% (deceleration).
  • Engine coolant temperature is greater than 75°C (167°F).
  • Engine speed is between 1000 RPM and 1250 RPM.
  • IAC position is steady.
  • MAP steady between 15 and 70 kPa.
  • Vehicle speed is greater than 25 mph during deceleration.
  • BARO sensor greater than 70 kPa.
  • MAP changes monitored during EGR flow test indicate insufficient EGR flow.
  • The vehicle will need to be driven above 50 mph, and then allowed to decelerate. When the vehicle is decelerating while meeting all of the criteria listed above, the PCM will enable the test to run. When the test runs, you will see the Desired EGR parameter and the Actual EGR position on the scan tool change from 0 to a calibrated value above 0.
Action Taken When the DTC Sets

  • The PCM will illuminate the MIL during the first trip in which the diagnostic test has been run and failed.
  • The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.
Conditions for Clearing the MIL/DTC

  • The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
  • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
  • The DTC can be cleared by using a scan tool.
 

CC'S95GT

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Circuit Description
For a more complete overview and system description, refer to EVAP Control System / Description and Operation .
The evaporative system includes the following components:
  • The fuel tank.
  • The EVAP vent valve/solenoid.
  • The fuel tank pressure sensor.
  • The fuel pipes and hoses.
  • The fuel fill cap.
  • The EVAP vapor lines
  • The EVAP purge lines.
  • The EVAP canister.
  • The EVAP canister purge valve/solenoid.
The EVAP SMALL LEAK TEST is based on applying vacuum to the EVAP system and monitoring vacuum decay. The PCM monitors vacuum level via the Fuel Tank Pressure sensor input. At an appropriate time, the EVAP purge solenoid and the EVAP vent solenoid are turned on allowing engine vacuum to draw a small vacuum on the entire evaporative emission system. After the desired vacuum level has been achieved, the EVAP purge solenoid is turned off, sealing the system. A leak is detected by monitoring for a decrease in vacuum level over a given time period, all other variables remaining constant. A small leak in the system will cause DTC P0442 to be set.

Conditions for Running the DTC

  • No TP sensor, ODM, IAT sensor, or MAP sensor DTCs set.
  • The DTC P0440 diagnostic test has passed.
  • Start-up engine coolant temperature is not more than 4°C and 30°C (40°F 86°F).
  • Start-up engine is not more than 8°C (14°F).
  • Start-up Intake air temperature not more than 2°C and 30°C (40°F and 86°F).
  • Start-up intake air temperature not more than 2°C (4°F).
  • Fuel tank level is between 15% and 85%.
  • BARO is greater than 75 kPa.
Conditions for Setting the DTC
A vacuum decay condition indicating a small leak is detected during the diagnostic test.

Action Taken When the DTC Sets

Important: Although these diagnostics are considered type A, they act like type B diagnostics under certain conditions. Whenever the EVAP diagnostics report that a system has passed, or if the battery has been disconnected, the diagnostic must fail during 2 consecutive cold start trips before setting a DTC. The initial failure is not reported to the diagnostic executive or displayed on a scan tool. A passing system always reports to the diagnostic executive immediately.


  • The PCM will illuminate the MIL during the first trip in which the diagnostic test has been run and failed.
  • The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.
Important: Although these diagnostics are considered type A, they act like type B diagnostics under certain conditions. Whenever the EVAP diagnostics report that the system has passed, or if the battery has been disconnected, the diagnostic must fail during two consecutive cold start trips before setting a DTC. The initial failure is not reported to the diagnostic executive or displayed on a scan tool. A passing system always reports to the diagnostic executive immediately.

Conditions for Clearing the MIL/DTC

  • The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
  • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
  • The DTC can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.
Diagnostic Aids
Check for the following conditions:

  • Cracked or punctured EVAP canister.
  • Damaged source vacuum line, EVAP purge line, EVAP vent hose or fuel tank vapor line.
  • Poor connection at PCM.
Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.

  • Damaged harness.
Inspect the wiring harness to the EVAP vent solenoid EVAP purge solenoid and the fuel tank pressure sensor for an intermittent open or short circuit.

Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table:

  1. The Diagnostic System Check prompts you to complete some of the basic checks and store the freeze frame and failure records data on the Scan Tool if applicable.
  2. If a vent valve or EVAP purge valve electrical malfunction is present, the purge system will not operate correctly. Repairing the electrical malfunction that caused the additional DTC to set will very likely correct the condition that set this DTC.
  3. Checks for a fuel tank pressure sensor stuck high condition. The fuel tank pressure must be relieved by removing the canister line from the fuel tank or EVAP canister. The fuel fill cap will not relieve the tank due to a check valve in the filler neck. the check valve seals when pressure is applied to prevent vapors from escaping through the filler neck. The Scan Tool should read within ±-1.0 in. H2O of the specified value.
  4. Verifies that the fuel tank pressure sensor accurately reacts to EVAP system pressure changes. The EVAP station is pressurizing a sensor that normally reads vacuum. The tech II reads high pressure at 0 volts and high vacuum at 5 volts. The Tech II can only read a max pressure of 6.0 inches of H2O (0 Volts). However the EVAP Service station can pressurize the system to much higher pressures. The Scan Tool value should be within ±-0.5 of the specified value.
  5. Checks for a small leak in the EVAP system.
  6. Checks for a leak in the Canister, vent line, or a leaking EVAP Vent Valve.
  1. Checks for a leaking or stuck open EVAP canister purge valve/solenoid. The scan tool should read within ±1.0 in. HG of the specified value.
  1. The EVAP station is pressurizing a sensor that normally reads vacuum. The Tech II reads high pressure at 0 volts and high vacuum at 5 volts. The Tech II can only read a max pressure of 6.0 inches of H2O (0 Volts). However the EVAP Service station can pressurize the system to much higher pressures. The Scan Tool value should be within ±0.5 of the specified value.
 

CC'S95GT

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PO1404
Circuit Description
The PCM monitors the EGR valve pintle position input to ensure that the valve responds properly to commands from the PCM. When the ignition switch is turned ON, the PCM learns the EGR closed valve pintle position. The PCM compares the learned EGR closed valve pintle position to the Actual EGR position when the EGR valve is commanded closed. If the Actual EGR position indicates that the EGR valve is still open when the PCM is commanding the EGR valve closed, DTC P1404 will set.

Conditions for Running the DTC
  • No TP, VSS, Misfire, IAT, MAP, Idle Speed, Fuel Injector, ECT, CKP, or MAF sensor DTCs set.
  • System voltage is between 10 volts and 16 volts.
Conditions for Setting the DTC

  • EGR Feedback is 0.2 volt greater than the EGR Closed Valve Pintle Position when the Desired EGR Position is commanded to 0 percent
  • The above condition is present for longer than 20 seconds.
Action Taken When the DTC Sets

  • The PCM will illuminate the MIL during the first trip in which the diagnostic test has been run and failed.
  • The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.
Conditions for Clearing the MIL/DTC

  • The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
  • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
  • The DTC can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.
Diagnostic Aids
Check for the following condition(s):

  • Excessive deposits on the EGR valve pintle or seat - Remove the EGR valve and check for deposits that may interfere with the EGR valve pintle extending completely or cause the pintle to stick.
  • Poor connections at PCM or EGR valve - Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
  • Damaged harness - Inspect the wiring harness for damage. If the wiring appears to be OK, connect J 39200 DMM and check circuit continuity while moving connectors and wiring harnesses related to the EGR valve. A change in the DMM display will indicate the location of the malfunction.
Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table:

  1. Verifies that the malfunction is present.
  1. If DTC P1404 will only set under certain conditions, the malfunction may be intermittent; refer to Diagnostic Aids in DTC P1404. If an intermittent wiring problem is not present, check for a poor connection at the PCM or the EGR valve. If the connections are OK and DTC P1404 continues to set, replace the EGR valve.
  1. This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.
 

CC'S95GT

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P1441
System Description
For a more complete overview and system description, refer to Evaporative Control System / Description and Operation .
The evaporative system includes the following components:
  • The fuel tank.
  • The EVAP canister vent valve/solenoid.
  • The fuel tank pressure sensor.
  • The fuel pipes and hoses.
  • The fuel fill cap.
  • The EVAP vapor lines.
  • The EVAP purge lines.
  • The EVAP canister.
  • The EVAP canister purge valve/solenoid.
The Powertrain Control Module (PCM) supplies a ground to energize the EVAP purge valve (purge on). The EVAP purge valve control is Pulse Width Modulated (PWM) or turned on and off several times a second. The duty cycle (pulse width) is determined by engine operating conditions including load, throttle position, coolant temperature and ambient temperature. The duty cycle is calculated by the PCM and the output is commanded when the appropriate conditions have been met. The system checks for conditions that cause the EVAP system to purge continuously by commanding the EVAP vent valve ON (Closed) and the EVAP purge valve OFF (Closed). If vacuum level in the fuel tank increases during the test, a continuous purge flow condition is indicated. This can be caused by any of the following conditions:

  • EVAP purge valve leaking internally.
  • EVAP purge and engine vacuum lines switched at the EVAP purge valve.
  • EVAP purge valve control circuit grounded.
If any of these conditions are present, DTC P1441 will set.

Conditions for Running the DTC

  • No ECT, IAT, MAP, TP, MAF sensor, VSS, HO2S, Misfire, Fuel Trim, Injector circuit, EGR Pintle Position DTCs set.
  • All conditions for DTC P0440, P0442 and P0446 diagnostic tests have been met and passed.
  • Start-up engine coolant temperature is not more than 4°C and 30°C (40°F 86°F).
  • Start-up engine is not more than 8°C (14°F).
  • Start-up Intake air temperature not more than 2°C and 30°C (40°F and 86°F).
  • Start-up intake air temperature not more than 2°C (4°F).
  • Fuel tank level is between 15% and 85%.
  • BARO is greater than 75 kPa.
Conditions for Setting the DTC
A continuous open purge flow condition is detected during the diagnostic test (fuel tank pressure decreases to less than -11 in. H2O.

Action Taken When the DTC Sets

  • The PCM will illuminate the MIL during the first trip in which the diagnostic test has been run and failed.
  • The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.
Important: Although these diagnostics are considered type A, they act like type B diagnostics under certain conditions. Whenever the EVAP diagnostics report that the system has passed, or if the battery has been disconnected, the diagnostic must fail during two consecutive cold start trips before setting a DTC. The initial failure is not reported to the diagnostic executive or displayed on a scan tool. A passing system always reports to the diagnostic executive immediately.

Conditions for Clearing the MIL/DTC

  • The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
  • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
  • The DTC can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.
Diagnostic Aids
Check for the following conditions:

  • Poor connection at the PCM - Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
  • Damaged harness - Inspect the wiring harness for damage.
  • If the harness appears to be OK, connect the J 41413 to the EVAP service port, pressurize the EVAP system to 10 in. H2O and observe the Fuel Tank Pressure display on the scan tool while moving connectors and wiring harnesses related to the EVAP purge valve. A sudden change in the display will indicate the location of the malfunction.
  • Incorrect vacuum line routing - Verify that the source vacuum line routing to the EVAP purge valve is correct and that the EVAP purge and source vacuum lines to the EVAP purge valve are not switched.
  • Malfunctioning or damaged canister.
Use the following procedure to check for a carbon release condition:

  1. Turn OFF the ignition switch.
  2. Remove the EVAP purge valve.
  3. Lightly tap the EVAP purge valve on a clean work area looking for carbon particles exiting either of the vacuum ports.
  4. If no carbon release is evident, reinstall the components and continue with the DTC P1441 table. If carbon is being released from either component, continue with this service procedure.
  5. Remove the charcoal canister from the vehicle.
  6. Ensure that the main cylinder valve is turned off on the J 41413 EVAP purge/pressure diagnostic station.
  7. Disconnect the black hose that connects the nitrogen cylinder to the EVAP purge/pressure diagnostic station at the pressure regulator by unscrewing the knurled nut on the regulator. No tools are required to remove the black hose from the regulator.
  8. Using a section of vacuum line, connect one end over the open threaded fitting of the EVAP purge/pressure diagnostic station pressure regulator.
  9. Connect the remaining end to the EVAP purge valve end of the EVAP purge line at the vehicle and turn on the main nitrogen cylinder valve. Continue to blow any debris from the purge line for 15 seconds.
  10. Return the EVAP Pressure/Purge Diagnostic Station to its original condition by re-installing the black hose that was disconnected in step 7.
  11. Replace the following components:
    • The EVAP purge valve.
    • The EVAP canister.
  1. Proceed with the DTC P1441 diagnostic table.
Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to set occurs. This may assist in diagnosing the condition.

Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table:

  1. The Diagnostic System Check prompts you to complete some of the basic check and store the freeze frame and failure records data on the Scan Tool if applicable.
  2. If an EVAP purge valve electrical malfunction is present, the purge system will not operate correctly. Repairing the electrical malfunction will very likely correct the condition that set this DTC.
  3. Checks for a Fuel Tank Pressure sensor stuck high condition. The fuel tank pressure must be relieved by removing the canister line from the fuel tank or EVAP canister. The fuel fill cap will not relieve the tank due to a check valve in the filler neck. The check valve seals when pressure is applied to prevent vapors from escaping through the filler neck. The scan tool should read within ±1.0 in. H2O of the specified value.
  4. Checks for a leaking or stuck open EVAP canister purge valve/solenoid. the scan tool should read within ±1.0 in. HG of the specified value.
  5. Verifies that the fuel tank pressure sensor accurately reacts to EVAP system pressure changes. the EVAP station is pressurizing a sensor that normally reads vacuum. The Tech II reads high pressure at 0 volts and high vacuum at 5 volts. The Tech II can only read a max pressure of 6.0 in. of H2O (0 Volts). However the EVAP Service Station can pressurize the system to much higher pressures. The Scan Tool value should be within ±0.5 of the specified value.
  6. If the EVAP purge and engine vacuum lines are switched at the EVAP Purge Valve/Solenoid, the valve/solenoid will leak vacuum.
  1. The EVAP station is pressurizing a sensor that normally reads vacuum. The Tech II reads High pressure at 0 volts and high vacuum at 5 volts. The Tech II can only read a max pressure of 6.0 in. of H2O (0 Volts). However the EVAP Service Station can pressurize the system to much higher pressures. The Scan Tool value should be within ±0.5 of the specified value.
 

CC'S95GT

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PO300
Circuit Description
The PCM has the ability to detect a misfire by monitoring the 3X reference and camshaft position input signals from the Ignition Control Module. The PCM monitors crankshaft speed variations (reference period differences) to determine if a misfire is occurring.
If 2% or more of all cylinder firing events are misfires, emission levels may exceed mandated standards. The PCM determines misfire level based on the number of misfire events monitored during a 200 engine revolution test sample. The PCM continuously tracks 16 consecutive 200 revolution test samples. If 22 or more misfires are detected during any 10 of the 16 samples, DTC P0300 will set. If the misfire is large enough to cause possible three-way catalytic converter damage, DTC P0300 may set during the first 200 revolution sample in which the misfire was detected. In the case of a catalyst damaging misfire, the MIL will flash to alert the vehicle operator of the potential of catalyst damage.

Conditions for Running the DTC
  • No VSS, Transmission, TP sensor, Fuel trim, Fuel injector, MAP sensor, EVAP, HO2S, IC/Bypass line monitor, EGR flow, EGR pintle position, ECT sensor, CKP sensor CMP sensor, or MAF sensor DTCs set.
  • Engine speed between 550 and 5900 RPM.
  • System voltage between 9 and 16 volts.
  • The ECT indicates an engine temperature between -6°C (21°F) and 120°C (248°F).
  • Throttle angle steady.
Conditions for Setting the DTC
The PCM is detecting a crankshaft RPM variation indicating a misfire sufficient to cause three-way catalytic converter damage or emissions levels to exceed mandated standard.

Action Taken When the DTC Sets

  • The PCM will illuminate the MIL during the second consecutive trip in which the diagnostic test has been run and failed.
  • The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.
Conditions for Clearing the MIL/DTC

  • The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
  • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
  • The DTC can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.
Diagnostic Aids
The scan tool provides information that can be useful in identifying the misfiring cylinder. If the DTC P0300 is currently stored as Test failed since code clear, the misfire history counters (Misfire Hist #1 - #6) will still contain a value that represents the level of misfire for each cylinder.
The scan tool displayed misfire counter values (Misfire Hist. #1 through #6) can be useful in determining whether the misfire is isolated to a single cylinder or to a cylinder pair (cylinders that share an ignition coil- 1/4, 2/5, 3/6.) If the largest amount of activity is isolated to a cylinder pair, check for the following conditions:

  • Secondary Ignition Wires: Check wires for affected cylinder pair for disconnected ignition wires or for excessive resistance. The wires should be 600 ohms per foot (1968 ohms per meter).
  • Damaged Or Faulty Ignition Coil: Check for cracks, carbon tracking or other damage. Also check coil secondary resistance. Secondary resistance should be between 5000 ohms and 7000 ohms (5K ohms and 7k ohms).
  • Substitute a Known Good Coil: Swap ignition coils and retest. If the misfire follows the coil, replace the ignition coil.
If the misfire is random, check for the following conditions:

  • System Grounds: Ensure all connections are clean and properly tightened.
  • MAF: A Mass Air Flow (MAF) sensor output that causes the PCM to sense a lower than normal air flow will cause a lean condition.
  • Air Induction System: Air leaks into the induction system which bypass the MAF sensor will cause a lean condition. Check for disconnected or damaged vacuum hoses, incorrectly installed or faulty crankcase ventilation valve, or for vacuum leaks at the throttle body, EGR valve, and intake manifold mounting surfaces.
  • Fuel Pressure: Perform a Fuel System Pressure Test . See: Engine, Cooling and Exhaust\Engine\Fuel Pressure\Testing and Inspection\Fuel System Pressure Test
A faulty fuel pump, plugged filter, or faulty fuel system pressure regulator will contribute to a lean condition.

  • Injector(s): Perform Injector Coil and/or Balance Test to locate faulty injector(s) contributing to a lean or flooding condition. In addition to the above test, check the condition of the injector O rings.
  • EGR: Check for leaking valve, adapter, or feed pipes which will contribute to a lean condition or excessive EGR flow.
Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table:

  1. A malfunctioning injector circuit, crankshaft position system variation not learned condition, or incorrect rough road data from the EBCM may cause a misfire DTC to be set. If any of the indicated DTCs are set with DTC P0300, diagnose and repair the other DTC before using the DTC P0300 table.
  2. The Misfire Current Cyl # display may normally display a small amount of activity (0 - 10 counts) but should not steadily increment during an entire 200 revolution test sample period.
  3. Depending on the cause of the misfire, the Misfire History Cyl # counter will display a very large number for the misfiring cylinder(s); values for the non-misfiring cylinders will be less than 1/2 as great as the misfiring cylinder(s). When investigating a misfire, always start with items associated with the cylinder(s) that has the largest number of counts stored in the Misfire History Cyl # counter.
  4. If the misfiring cylinders are companion cylinders, the condition is most likely linked to the ignition system.
  1. Check for poor terminal connection, grooves, corrosion, pitting, loose fit.
  1. Check for the following conditions that may contribute to the engine misfire: engine oil pressure, damaged accessory drive belt or pulley, damaged driven accessory (generator, water pump drive belt tensioner, etc.) Loose or broken motor mount(s).
 

sn95jones

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Damn man my ex has an '04 Grand Am with the 3400 motor and she's had to replace the fuel tank twice and the motor keeps throwing codes too. Once those Pontiacs start throwing codes it will keep doing it.
I am willing to bet 90% of your codes are related to one issue, if you having a problem with it staying running, doesn't seem to have 100% power and will stall out at idle then most likely a crank position sensor.
What is possible with a bad crank sensor it could have damaged your catalytic converters thus also triggering exhaust codes.
 
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KillNThrill24

KillNThrill24

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Wow thanks CC I appreciate all of that! I'll get checkin right away man. And Jonesy I couldn't agree more man, this thing just keeps throwing codes.. In the even that the Check Engine light goes out I literally start to worry..... Time to go see if I can figure this out.. Thanks guys!

And I know MOST of this engine, but not all of it. The crank sensor, isn't that the one on the passenger side of the block? Below the intake manifold and next to the timing cover? That blue sensor I believe it is
 
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KillNThrill24

KillNThrill24

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Well my old man and I took a look at it today and then I consulted my good friend who is a mechanic (and he will be looking at it sooner or later) and well the problems are it wont stay running, it's got a leak on the passenger side that the whole back of the block is soaked in I think oil, and it's dripped down onto the subframe, which slowly drips to the ground. It's got a lot of milky moisture in the valve cover (which may be normal I realize...) and right before we shut it down the RPM's shot up to 1500-2000 pulsing back and forth and it smelled like sulfuric, or rotten eggs, like you guys suggested.... My buddy thinks I may have a cracked block.


I think this car has finally croaked.....
 

CC'S95GT

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me too. My first car was a 68 firebird. but my favorite car I had was a 83 Grand Prix with t-tops and snow flake wheels.
 

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