Weird Problem..... Just got A LOT WORSE!!! (PART 2)

[Quarter Horse]

Ok, Sorry Guys I'm Really NOT trying to be a Thread Whore but my Fan issue just turned into something A LOT worse!!! I figured it would just be easier to start a new thread so People didn't have to read through unnecessary posts.
So today I took the 95 Stang to Work like Normal(The Fan has been acting the same.... With running kinda erratic and staying on right from start up), But here's were things get WORSE! On my way home I did a quick stop @ the Bank, Came back to the car and fired it up. It shot up to about 2200RPMS and then started to idle hunt Very Badly! I was only a few blocks from the house so I figure I will limp it home.
The drive home was quite a PITA, anytime I pushed the clutch in it stalled, it would start right back up but I kept having to play with the Throttle to keep it running.(Almost like it was in limp mode??) Engine felt like it was running on 6 cyls and was putting out a Horrible smell (Almost like when gas goes bad..... But I know that's not it, Been on the same tank all week). Not sure if it was in Limp mode and the CPU is just really Retarding the engine or what??? The Check engine light was on all the way home from the bank.
So, Once I got it in the Drive way it was staying running (Barely) so I looked the engine over the obvious stuff and sprayed Carb Cleaner around Vac Hoses to see if there were any Vac leaks and all checks out ok so far.
From there I shut the car off & Pulled codes, Here is what it is coming back with;

556 - Primary Fuel Pump circuit failure

and then in the Stored Memory;

512 - Keep Alive Memory test failed (This might be from me previously pulling the wire during the code reading process to erase the stored codes? IDK???)

What do you all think...... Fuel Pump is bad, Dizzy going out? PLEASE HELP, I have No Idea where to go from here?????

 

[CC'S95GT]

Aaaand the hits just keep coming.
I don't think it's the FP or dizzy.
It's starting to sound like a ground or aother wiring prob.
Ck the grounds,batt-engine, batt-chassis, engine - chassis.
Also ck the positive wire between the battery and fuse box. make sure the connections are tight and there is no corrosion under the insulation.

 

[Quarter Horse]

Aaaand the hits just keep coming.
I don't think it's the FP or dizzy.
It's starting to sound like a ground or aother wiring prob.
Ck the grounds,batt-engine, batt-chassis, engine - chassis.
Also ck the positive wire between the battery and fuse box. make sure the connections are tight and there is no corrosion under the insulation.

Tell Me about it!!!
Ok, I will look over/replace any bad grounds or Wires.(This is gonna be like shooting in the Dark) Question though, Why would it keep given me the 556 code if it's not the Pump or fuel delivery problem? This is the 2nd time (I cleared all the codes from the 1st time) it has thrown that same 556 code.
Guess I could put a Fuel Pressure gauge on it and see what I got? Duhhh.... Don't know why I didn't think of this earlier, Cuz I do have one out in the Garage.

 

[CC'S95GT]

I'm thinking the computer isn't getting the voltage it needs. and that's why it's throwing 556. I hope

 

[ttocs]

that should be easy enough to check with a meter to see if its got enough power. Grounds are not something you can visually look at to check if they are good/bad unless the wires are just so visably corroded that its obvious. So if you do want to check the grounds first just grab and see if moves at all(should not move ANY). If it is tight go ahead and remove it, clean the areas of contact with some sand paper and then tighten them back up.

other then a bad ground I am not sure how the ECU would loose enough voltage to cause problems and if the ECU was not getting enough power or had a bad ground I would have to think that it would probably throw more then one code. How old is your fuel pump? Can you or did you check your fuel pressure?

 

[RichV]

Aren't fans and fuel pump controlled from the CCRM? Not sure if you tried swapping one of those.

Definitely check the FP if you have a gauge, should be 35-40# without a vac line to the FPR.

 

[Quarter Horse]

that should be easy enough to check with a meter to see if its got enough power. Grounds are not something you can visually look at to check if they are good/bad unless the wires are just so visably corroded that its obvious. So if you do want to check the grounds first just grab and see if moves at all(should not move ANY). If it is tight go ahead and remove it, clean the areas of contact with some sand paper and then tighten them back up.

other then a bad ground I am not sure how the ECU would loose enough voltage to cause problems and if the ECU was not getting enough power or had a bad ground I would have to think that it would probably throw more then one code. How old is your fuel pump? Can you or did you check your fuel pressure?

Thanks for your input. :thumbsup: Ya I am going to look over all the Grounds and make sure they are tight and all good. The fuel Pump is Factory, I haven't had a chance to check fuel PSI yet but I will, What kind of Pressure should I be seeing out of it? The Pump has a 133,000 miles on it as well.

 

[Quarter Horse]

Aren't fans and fuel pump controlled from the CCRM? Not sure if you tried swapping one of those.

Definitely check the FP if you have a gauge, should be 35-40# without a vac line to the FPR.

Thanks Rich for Posting! That's VERY interesting about the CCRM. Can anyone else confirm this as well? If this is so, it would make a lot of sense seeings how the Fan does act weird as far as cycling ON/OFF goes(Was thinking it was the ECT and I bought a New one that I will still through in there). I will try to get some time today after work to check the Fuel Pressure and see what I got, I'll report back once I have that done. :thumbsup:

***Again, Thanks for all the Help Guy's, it's very Appreciated!! :smiley:

 

[ScottyDsntKnow]

Not sure about what you did in the other thread. If you haven't replaced the dizzy that would be my first stop and do the coil as well. The dizzys are notorious for going out in these cars and they usually take the coil with them. After that... could be a CCRM issue or it very well might be a fuel pump or shot injector or something else. You should have seen the shape my 60k miles new injectors were when I pulled them out of my old Cobra. Literally falling apart. When was the last time you did your fuel filter? And it would be a good excuse now to upgrade the fuel pump to something that'll support more power later as well. Fuel pressure should be right around 40 psi at idle btw.

 

[CC'S95GT]

the CCRM houses the hi speed and low speed fan relays, fuel pump relay and the a/c relay.

 

[Quarter Horse]

Not sure about what you did in the other thread. If you haven't replaced the dizzy that would be my first stop and do the coil as well. The dizzys are notorious for going out in these cars and they usually take the coil with them. After that... could be a CCRM issue or it very well might be a fuel pump or shot injector or something else. You should have seen the shape my 60k miles new injectors were when I pulled them out of my old Cobra. Literally falling apart. When was the last time you did your fuel filter? And it would be a good excuse now to upgrade the fuel pump to something that'll support more power later as well. Fuel pressure should be right around 40 psi at idle btw.

Thanks for Posting...... I have not Changed the Dizzy..... But did installed a New Coil (MSD Blaster). More Details in a Sec......

the CCRM houses the hi speed and low speed fan relays, fuel pump relay and the a/c relay.

Thanks CC! :thumbsup:

 

[Nightmare]

the CCRM houses the hi speed and low speed fan relays, fuel pump relay and the a/c relay.

My guess is this.......

 

[Quarter Horse]

ALRIGHT THIS SHIT IS REALLY PISSING ME OFF GUY'S!!!!!

So I got home from work today and had a few free minuets to wrench on the Car. Hook my fuel PSI gauge up, turned KOEO and PSI is about 35psi, Start the Car(Which is Running Perfectly FINE now ) and it's about the same, maybe a tad lower 32-35psi? With it Running I give it some Throttle and it drops a Bit then goes back up..... Unplug the FPR vacume line and the gauge goes straight to 40psi and does NOT Budge even revving the PISS put of the Engine!!! Looked over all the Grounds(Seem to be ok??), if anything there a tad on the small side. I could swap them out for Beefier ones?

So at this Point I have NO FU[KING IDEA where to go?? Maybe a Clogged fuel filter?

 

[Quarter Horse]

My guess is this.......

Ya, Might be Right.... But it's like, do I just start throwing a Shit load of parts at it?? As it stands I have only owned the Car for a Couple months and I have replaced........

Oil & Filter, Plugs & Wires, Cap & Roter, Coil, Radiator, thermostat.... Now Granted those things were more of a Tune up. But I am also in the process of changing the ECT Sensor(for the fan running right from start up) and Both 02 Sensors for a Lean Code.

Now with this Running Problem I'm looking at the very least changing the Fuel Filter(No big deal on this as I should have done it when I did the tune up), Possibly the CCRM, Maybe the Dizzy, Maybe the Fuel Injectors, All new Ground Cables, and then I guess the Fuel Pump too! WTF????

***Sorry Guy's, Just Venting/Ranting here....... Really Pisses Me off when I can't figure something out. It seems like Just when I get one issue "Almost" ironed out, ANOTHER One pops up!

 

[RichV]

That's fine dude. When the vac line is unplugged it should be 40psi steady. With the vac plugged in it will go up/down with the throttle.

 

[toyman]

ALRIGHT THIS SHIT IS REALLY PISSING ME OFF GUY'S!!!!!

So I got home from work today and had a few free minuets to wrench on the Car. Hook my fuel PSI gauge up, turned KOEO and PSI is about 35psi, Start the Car(Which is Running Perfectly FINE now ) and it's about the same, maybe a tad lower 32-35psi? With it Running I give it some Throttle and it drops a Bit then goes back up..... Unplug the FPR vacume line and the gauge goes straight to 40psi and does NOT Budge even revving the PISS put of the Engine!!! Looked over all the Grounds(Seem to be ok??), if anything there a tad on the small side. I could swap them out for Beefier ones?
So at this Point I have NO FU[KING IDEA where to go?? Maybe a Clogged fuel filter?

Those fuel pressures are within spec and the FPR is working as it should based on what you stated. Maybe I missed it but have you checked the signal voltage from the TPS? When you do the test use the ground to the TPS and not on the engine itself. KOEO the TPS closed throttle should be about 1v and as you open the throttle the voltage increase should be smooth (no blips) and at WOT should read around 4.7v. Under normal operating temps the fan isn't too likely to be on except if the A/C is on. That triggers the Hi fan relay. The low fan comes on at about 220* and will stay on until the coolant temp falls to 205*. It's also possible that the fan motor pigtail has overheated over the years and an internal short is occurring. That applies equally to the fan motor itself.

 

[Quarter Horse]

That's fine dude. When the vac line is unplugged it should be 40psi steady. With the vac plugged in it will go up/down with the throttle.

So the Fuel Pump & FPR is Good Correct?

Those fuel pressures are within spec and the FPR is working as it should based on what you stated. Maybe I missed it but have you checked the signal voltage from the TPS? When you do the test use the ground to the TPS and not on the engine itself. KOEO the TPS closed throttle should be about 1v and as you open the throttle the voltage increase should be smooth (no blips) and at WOT should read around 4.7v. Under normal operating temps the fan isn't too likely to be on except if the A/C is on. That triggers the Hi fan relay. The low fan comes on at about 220* and will stay on until the coolant temp falls to 205*. It's also possible that the fan motor pigtail has overheated over the years and an internal short is occurring. That applies equally to the fan motor itself.

Thanks for posting, I have Not checked the TPS as you mentioned above. But would/could that even be the Running issue I explained above?(There have been no tps codes at all) When the Engine started "Acting up" it was like someone cut the ignition and it was Dieseling all while still trying to run. (If that makes ANY sense??) It also was kicking out a HORRIBLE Smell..... What could that smell be from?

The Fan Problem did not start until I changed out the Radiator and Thermostat.(Installed a 180* one) I never unplugged the CCRM, Just moved it out of the way. Ever since then the Fan comes on as soon as I turn the Key on and stays on for awhile then will start cycling. The AC is NOT on, and both Fan speeds do work because when I pull codes I can hear the Fan switch speeds b4 it starts spitting out codes. For this problem I was/am going to change out the ECT Sensor as I did get (2) codes that said it was out of spec. (For more on these codes please see "Weird Fan Issue" thread just below this one. But b4 I could get into doing this sensor swap this whole other nightmare popped up. Now I'm kinda worried to even drive this thing until I figure out what the Hell is going on???

 

[RichV]

So the Fuel Pump & FPR is Good Correct?

Sounds like they are OK from this test.

Dieseling is not something you see from EFI vehicles a whole lot. Can you smell the vac line that goes to the FPR? Does it smell like fuel? Or can you see liquid? I have seen FPRs leak and you can suck fuel into the intake from the vac line, and if you timing is not set correctly it can do what you're describing. Or a leaky injector. If the FPR needs replaced, just get a stocker replacement.

Here's what I would check/do.
1. Verify timing is set to 10* BTDC, spout out. Do this wen the engine is warmed up.
2. Replace fuel filter if you have not in a while.
3. Get some injector cleaning solution, I like Valvoline products, and put it in the tank.
4. Drive it hard for like an hour.

See if it makes a difference. I hate problems like this, issues that come from all angles is very tough to diagnose. Specially on the internet.

 

[mcglsr2]

Sorry man, this stuff is hard to track down I didn't see your other thread yet, so if I say something already addressed over there, I apologize. Here's the things I think it might be:

• Fuel filter
• Bad fuel pump/shorted wire
• Bad O2 sensor(s)?
• Bad coil/rotor
• Bad coolant sensor (there are 2, one for the ECU and one for the gauge)
• Vacuum leak
• Bad Alternator/Voltage regulator (ECU and stuffs rely heavily on voltage regulation)

For it to work as bad as you described one time, then to work fine the next, that sounds to me like an intermittent issue somewhere...like something is on it's way to being bad, or perhaps a short somewhere.

 

[Quarter Horse]

Sounds like they are OK from this test.

Dieseling is not something you see from EFI vehicles a whole lot. Can you smell the vac line that goes to the FPR? Does it smell like fuel? Or can you see liquid? I have seen FPRs leak and you can suck fuel into the intake from the vac line, and if you timing is not set correctly it can do what you're describing. Or a leaky injector. If the FPR needs replaced, just get a stocker replacement.

Here's what I would check/do.
1. Verify timing is set to 10* BTDC, spout out. Do this wen the engine is warmed up.
2. Replace fuel filter if you have not in a while.
3. Get some injector cleaning solution, I like Valvoline products, and put it in the tank.
4. Drive it hard for like an hour.

See if it makes a difference. I hate problems like this, issues that come from all angles is very tough to diagnose. Specially on the internet.

Thanks Rich! :wink: I REALLY DO Appreciate all the Help.

Sorry man, this stuff is hard to track down I didn't see your other thread yet, so if I say something already addressed over there, I apologize. Here's the things I think it might be:

• Fuel filter
• Bad fuel pump/shorted wire
• Bad O2 sensor(s)?
• Bad coil/rotor
• Bad coolant sensor (there are 2, one for the ECU and one for the gauge)
• Vacuum leak
• Bad Alternator/Voltage regulator (ECU and stuffs rely heavily on voltage regulation)

For it to work as bad as you described one time, then to work fine the next, that sounds to me like an intermittent issue somewhere...like something is on it's way to being bad, or perhaps a short somewhere.

Thanks MC for Posting up! :smiley: Where is the 2nd ECT at? I know of the one right next to the water neck..... where is the other one located? Thanks

Ok, So a Bit of GOOD NEW'S Finally (At least for now :undecided: lol ) So I went ahead and Changed out the Fuel filter and also replaced the ECT Sensor (The one by the water neck) and So far..... So Good! The Fan came right on with the key the 1st time, But I think the CPU needed to correct itself or something because the Fan is Back to working like Normal now!!! :headbang: The Hi-Speed fan even comes on now when I turn on the AC and it NEVER did that before! :smiley: (Didn't really care because the AC doesn't work anyways, But at least I know it's working "Correctly" now)
So as of right now all seems to be good (KEEPING MY FINGERS CROSSED), I will take your advise Rich and Dump some fuel system cleaner in the tank as well. I still have the 02 Sensor's to swap out but she's Back to Screaming like a Raped Ape, OK.... Horse again!!! :grin:

*** I really want to Thank "EVERYONE" that Posted up to Help me out..... AND Listen to me Rant (Sorry about that) in Both threads. Hopefully I will be able to Re-Pay you all, in some form or fashion in the Future because I know 1st hand, Knowledge doesn't come Cheap!!! :thumbsup: