Casper the Cobra - Procharged 96' Cobra

[Venompower]

I had this same problem with my tps but it was only showing 5-6% while idling and only when it was hot. I replaced the sensor and it did the exact same thing because it ended up being the harness that was bad.

I'll keep my fingers crossed that it's something easy. The car is tuned, and while I assume the tune wouldn't mess with TPS signal... I'm not knowledgeable enough about tuning to know if this issue could be tune related.

 

[ttocs]

The tune would cause the tps to show the incorrect #'s, its just reading a sensor. Now a bad connection can show up as the wrong % for the tps and as I said this incorrect reading can/will throw the tune off.

 

[Venompower]

The tune would cause the tps to show the incorrect #'s, its just reading a sensor. Now a bad connection can show up as the wrong % for the tps and as I said this incorrect reading can/will throw the tune off.

So I think my understanding of the TPS (%) was incorrect. It appears the scanner reads TPS voltage between 0V and 5V and then converts it to a percentage. So in my case I read it as TPS (%) 19.2 percent meaning the throttle body was open 19.2% on a scale of 0-100. In reality it was 5V x .192 = 0.96V which is within the range for idle. So I still plan on checking it with a volt meter to confirm.

 

[ttocs]

The tps is just a variable resistor that changes resistance as the throttle is applied. The ecu measures this by the change in voltage it reads across it. Now with your foot off of the gas(running or not) the tps should show 0% if its like my holley ecu is. I have the throttle stop on mine set to hold it open 3-4% for idle but 20% is a fair amount of gas. Have you tested these voltages your listing? Tps is easy to test just stab the two outer wires on the harness(double check me on that) with a volt meter and then you move the throttle up/down to make sure its a smooth sweep it read and doesn't jump or have any dead spots.

 

[Venompower]

The tps is just a variable resistor that changes resistance as the throttle is applied. The ecu measures this by the change in voltage it reads across it. Now with your foot off of the gas(running or not) the tps should show 0% if its like my holley ecu is. I have the throttle stop on mine set to hold it open 3-4% for idle but 20% is a fair amount of gas. Have you tested these voltages your listing? Tps is easy to test just stab the two outer wires on the harness(double check me on that) with a volt meter and then you move the throttle up/down to make sure its a smooth sweep it read and doesn't jump or have any dead spots.

I'm going to tonight, I hadn't thought to do it yet when I assumed the scan tool was measuring the actual angle percentage as opposed to percentage of total voltage. I think LMR had a pretty good tutorial involving a sewing needle to volt meter and then grounding off the intake manifold. If I get around .96V I'll assume the scan tool measured correctly, and then I'll open the throttle body to see if the numbers increase smoothly.

 

[Venompower]

Checked voltage and got .94V at closed, and as I opened the throttle body it steadily increased up to a max of 4.75V.

Some have said that it may need an idle re-learn and that on our cars, that's disconnecting the battery for about ten minutes. Then starting the car with all accessories off and letting it idle 5-10 minutes, then turning AC on full and letting it idle another 5-10 minutes. Some have said if not done, the idle will never really be right.

 

[Venompower]

Small update:

Didn't think I would have time to get much of anything done on Mother's Day weekend, but the wife gave me the go ahead yesterday afternoon to do what I could while our youngest was napping. Got the new Bosch LSU 4.2 sensor installed, which was a little dicey for a bit. The BBK off-road H-pipe had a plug in the driver's side rear 02 bung that was Allen bolt and even after spraying it with PB Blaster it just didn't want to budge at all. Finally got out the breaker bar, and after gently asking it to cooperate I heard a loud pop which I assumed was something breaking... but was lucky that the plug easily unthreaded and was removed.

While I did this I tried to do the PCM idle learn procedure, but disconnecting the battery while I installed the sensor, and then once everything was done letting it idle 5-10 min with the accessories off and then another 5-10 minutes with AC set to full blast. It did idle smooth, but it still idles around 1k rpm. My AFR fluctuated between 13.4-14.8 at idle, and when given a rev went richer... so it would appear the sensor is working correctly.

Due to how long the sensor install went due to the Allen bolt plug I couldn't mess with it longer, but in the time it idled the fan never came on... so that's something to monitor. I'm also debating if I should take it to the local Mustang shop to have the adjustable clutch cable professionally adjusted, or if I should just buy an OEM non-adjustable clutch cable and use that. I can still adjust it at the firewall, but wouldn't have to adjust it at the clutch fork.

Edit: Ordered an OEM Ford non-adjustable clutch cable, going to remove the clip to allow it to work with the firewall adjustor, but don't want to mess with adjusting the end that connects to the clutch fork.

 

[DKblue98GT]

Sounds like progress. You are on the right track with the clutch cable.

 

[88stang88]

Before you know it you are going to run out of things to fix and I can have you head south to help sort out mine

 

[Venompower]

Before you know it you are going to run out of things to fix and I can have you head south to help sort out mine

I would love to help someone else out and be done with mine lol. You look like you are making great progress too! You might look into Team Z for the K-Member, that's what I have. They don't have anything on their site about a back order or build time...

 

[Venompower]

Sounds like progress. You are on the right track with the clutch cable.

I really hope so, I just feel like a single adjustment point at the firewall will be easier to utilize than trying to figure out how high up the cable end to tighten the lock nut...

 

[joe65]

I would love to help someone else out and be done with mine lol. You look like you are making great progress too! You might look into Team Z for the K-Member, that's what I have. They don't have anything on their site about a back order or build time...

I've bought my k member and A arms from them this past spring and they say when you order there could be a delay, but i've received stuff from them fast. Just saying.

 

[Venompower]

I haven’t even gone and looked but was wondering what all is involved with removing the intake manifold cover? I would like to get it powder coated wrinkle black instead of the current metallic grey if it’s not too much trouble.

The clutch cable arrived today along with the correct manifold cover plaque.

 

[88stang88]

I haven’t even gone and looked but was wondering what all is involved with removing the intake manifold cover? I would like to get it powder coated wrinkle black instead of the current metallic grey if it’s not too much trouble.

The clutch cable arrived today along with the correct manifold cover plaque.

It’s not hard at all. About 20 minutes worth of wrench time and it’s off.

 

[Venompower]

Saturday was raining and cold, and I had zero desire to work on the car… but yesterday was decent and warmer so I finally got around to replacing the adjustable clutch cable for an OEM cable. The job wasn’t bad, definitely needed a Dremel tool to cut the plastic housing off that connects to the firewall so that it would work with the adjustor and a crowbar made getting the end of the cable locked into the clutch fork a snap.

Took it for the longest drive to date, and noticed two things. One, I definitely need someone who knows suspension to go over the front as I was getting some weird pops and clunks as I drove. It didn’t feel unsafe, but it made more noises than I think it should even for coil overs. Two, she rips… I took it out on the highway by my neighborhood and did a pull in second gear from about 25 mph and as the rpms climb and the boost picks up it just puts you back in the seat. It’s definitely a different feeling from my old 03 Cobra swapped Mach 1, the roots blower gives immediate power and liked to spin, this car has a nice linear pull up to red line. The sound of the big red race blowoff valve when you shift is amazing as well.

Things left to do before summer driving season:

- Change Oil and Fuel Filter

- Get Suspension sorted

- Get Tires

- Install front fender liners so I can wash the car without hosing down the Anderson Motorsport Powerpipe filter which sits in front of the passenger side wheel.

- Decide if I want to remove the intake cover and have it power coated Wrinkle Black or just install the new OEM Cobra plaque and wait until fall.

 

[lwarrior1016]

So, did you get all the running issues sorted out? How did the oxygen sensor ordeal pan out?

 

[Venompower]

So, did you get all the running issues sorted out? How did the oxygen sensor ordeal pan out?

The oxygen sensors per the live data on my scan tool are registering, and while the engine idles right around 1k rpm it idles smooth and there is no hiccups in power delivery or driving. The Bosch LSU 4.2 is plugged into the rear driver 02 sensor bung and is working, at cold start the engine bounced between 14.7-14.8 and 13.4. Yesterday when driving I noticed it was in the 13's on the highway while cruising. Didn't have a chance to really look at AFR during the single pull I made or the boost gauge.

 

[joe65]

Sounds like a good drive! The weather here has also been off and on. For Colorado its not typical. Usually we are mostly sun and dry. I'm still on the Cobra hunt here. I have a few things brewing, we'll see what happens.

 

[Venompower]

Sounds like a good drive! The weather here has also been off and on. For Colorado its not typical. Usually we are mostly sun and dry. I'm still on the Cobra hunt here. I have a few things brewing, we'll see what happens.

Yeah I'm hoping the monsoon season passes and we can start getting some more consistently nice and warm weather. The Blow Off Valve is going to have to hold me over until I can afford an MKIV Supra or R32/33 GTR. I think my search will last a lot longer than yours though lol.

 

[Venompower]

So I posted in the "electrical" section, but thought I would ask here as well. Noticed on the last drive that neither my turn signals nor hazards worked and the relay did not make any clicking sound and the lights did not illuminate on the gauges. I do have the turn signal bulbs and tail lights work, am I correct to assume the flasher relay is probably bad? I pulled it, and ordered a replacement off Amazon today.