96' Procharged Cobra "Casper" Build

01silverstang

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For reference, I have BBK LT's, o/r X and it had Super 44s and my car was louder than yours it seems starting and at idle. Not sure why your seems quiet in comparison. Sorry, no video though. I have since put Stingers on and it's much louder and sounds better IMO.
Yeah, that's what I'm hearing... not sure if I should just take it to an exhaust shop to have all the connections gone through, new gaskets and have everything tightened up. Not sure what could be causing this... without triggering a code?
 

jman37

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I'm no expert or anything but my car still has the EGR system and all air pump stuff still in tact, though I can't imagine that making a difference. Before my tune I had a CEL for 02s since it has no cats and that was it.
 

01silverstang

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Ok so no arcing seen in the dark with the engine running... I did plug in my scan tool and here is the live data, can people smarter than me give me some guidance.

DTC_CNT 3
FUELSYS1 OL-DRIVE
FUELSYS2 - -
LOAD_PCT (%) 24.7
ECT (Degrees) 89
SHRTFT1 (%) 0.0
LONGFT1 (%) 0.0
SHRTFT2 (%) 0.0
LONGFT2 (%) 0.0
RPM 1026
VSS (MPH) 0
SPARKADV (Degrees) 16.5
IAT (Degrees Fahrenheit) 57
MAF (lbs/s) 0.02
TP (%) 19.2
AIR_STAT Off
02SLOC B1S12 - - B2S12 - -
02B1S1 (V) 0.000
SHRTFT B1S1 (%) 0.0
02B1S2 (V) 0.000
SHRTFT B1S2 (%) 0.0

My interpretation is that my MAF isn’t reading correctly and is a little low. It appears the 02 sensors are not plugged in and therefore I have no fuel trims. IAT looks good, Spark Advance looks good... vacuum on the boost gauge held steady at 22, so no apparent large vacuum leaks. I’m thinking I need to figure out where the connectors are for the 02’s and get them plugged back in and see how the live data changes, and then look into my MAF numbers more.
 
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DaveWertz

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I have MAC LT, MAC X-Pipe and SLP LM-1s and mine sounds very similar to yours at startup. Maybe a bit louder. But at WOT its insanely loud, sounds good but loud.
 

03cobra#2

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Ok so no arcing seen in the dark with the engine running... I did plug in my scan tool and here is the live data, can people smarter than me give me some guidance.

DTC_CNT 3
FUELSYS1 OL-DRIVE
FUELSYS2 - -
LOAD_PCT (%) 24.7
ECT (Degrees) 89
SHRTFT1 (%) 0.0
LONGFT1 (%) 0.0
SHRTFT2 (%) 0.0
LONGFT2 (%) 0.0
RPM 1026
VSS (MPH) 0
SPARKADV (Degrees) 16.5
IAT (Degrees Fahrenheit) 57
MAF (lbs/s) 0.02
TP (%) 19.2
AIR_STAT Off
02SLOC B1S12 - - B2S12 - -
02B1S1 (V) 0.000
SHRTFT B1S1 (%) 0.0
02B1S2 (V) 0.000
SHRTFT B1S2 (%) 0.0

My interpretation is that my MAF isn’t reading correctly and is a little low. It appears the 02 sensors are not plugged in and therefore I have no fuel trims. IAT looks good, Spark Advance looks good... vacuum on the boost gauge held steady at 22, so no apparent large vacuum leaks. I’m thinking I need to figure out where the connectors are for the 02’s and get them plugged back in and see how the live data changes, and then look into my MAF numbers more.
I see ect is only at 89. Get it up to full operating temp and log again.

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01silverstang

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I see ect is only at 89. Get it up to full operating temp and log again.

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Once I get it jacked up and make sure the 02’s are plugged in I will. I also got feedback that TPS is off, as it should be closer to zero at idle. Trying to determine if this is caused by the idle screw being off or if the TPS needs a relearn or is bad?
 

98 svt

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Once I get it jacked up and make sure the 02’s are plugged in I will. I also got feedback that TPS is off, as it should be closer to zero at idle. Trying to determine if this is caused by the idle screw being off or if the TPS needs a relearn or is bad?
Did you touch the idle screw?
 

01silverstang

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Did you touch the idle screw?
No I didn’t, but I found enough other strange stuff on this car that it could have been messed with by previous owner... I’m still at a loss for when and why they removed the plug from the top of the throttle body. It may also explain my hanging idle when putting the clutch in during the maiden voyage.
 

01silverstang

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Jacked up the car and tried to plug the 02 sensors in, but they didn't want to seat well. Was looking at Rock Auto and some were listed as downstream only, wondering if that's the problem, could these be the downstream and the connector is different? I'll order new NTK OEM 02 sensors but would rather not spend the $80 if I'm going to have the same issue...
 

DSG2003Mach1

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cant you look at the connectors and tell if they're right or not? I would think the up and down stream would have different connectors if nothing else
 

01silverstang

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cant you look at the connectors and tell if they're right or not? I would think the up and down stream would have different connectors if nothing else
I got so frustrated that I went back out and jacked it up again. Got the driver side connected, the passenger side sensor had bent pins which I couldn’t straighten out. Started it up and drive side registered on live data and the engine idle smoothed out immediately. I went ahead and ordered two NTK 02 Sensors from Rock Auto.

Did find out the Air Fuel gauge is not connected to the exhaust, so I’ll have to have a shop weld some Bungs in and buy the sensors.
 

BOTTLEFED5

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Man seems like someone really didn't know what the hell they were doing with this car lol. I think i might still have my old engine harness laying around, ill check.

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01silverstang

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Man seems like someone really didn't know what the hell they were doing with this car lol. I think i might still have my old engine harness laying around, ill check.

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Yeah the original owners put a lot of money into this car, the more recent owners did some strange stuff.

Working good for me

BBK X pipe

Thanks that’s good to know, mine is a BBK H-Pipe now that I’ve gotten under far enough to inspect.
 

01silverstang

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So went to the junkyard this weekend and managed to find a front passenger side ABS/Wheel Speed Sensor, $10 and I should be back in business with no ABS light. The current sensor wasn't well secured and the wheel rubbed through the wire.

My Amazon special LED fog light bulbs came, I was able to throw one in quickly to test and I think they look pretty good. Need to adjust the fog light and bumper to get better fitment, and need to do the re-pin under the center console so I can run the fogs with just the running lights.

fog-light.jpg


Hopefully the new NTK 02 Sensors will arrive this week, and I can find a way to adjust my idle screw without damaging it.
 

01silverstang

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Late to post but got a couple things done this weekend. My new OEM 02 sensors arrived, and I was able to get them both installed. The car still ran rough immediately after, but I'm assuming there is some amount of time for the PCM to start receiving the signal and then to make adjustments. I should have let it idle longer to verify, but got frustrated that it wasn't a more immediate change and moved on to other things I needed to do.

I removed the drivers side PCV from the vacuum line as others recommended earlier. I still need to find a place to mount my catch can which is rather large, but I have everything I need for that once I figure it out. I also removed the intake tube from the throttle body and hit it with some carb cleaner to make sure the blades weren't sticking. It appeared to be entirely closed and while I did PB blast the idle stop screw, adjusting it didn't seem to make a visual difference, I would have assumed based on the 19.2 (%) reading from live data on my scanner that the blades would appear to be open at idle, but they didn't. After some adjustment the percentage dropped to 18.6 (%) which makes me wonder if the TPS is faulty, or needs adjustment. I know the earlier SN95 were adjusted by loosening the screws and moving it until it read proper voltage. If it's not adjustable then the sensor may just be bad?

When re-tightening the intake elbow, it caused the lower connector to pop off after I went to start it... car sounded cammed and boost gauge was showing like 4-5 for vacuum. Got it reconnected well, and started it and it was very smooth. Being the scientist I am, I can not point to any specific cause because I didn't isolate each change like I should have lol.

I wasn't able to get the wideband running correctly, as I assumed it used a LSU 4.9 sensor, and found out it's old enough it uses the LSU 4.2 sensor. I couldn't find any cheap alternatives that looked trustworthy so I guess I'm out $80 for a Bosch unit. If anyone has used a cheaper alternative with good results please let me know.

I ended the day installing the passenger fog light bulb and re-pinning the harness while my son "drove" his Cobra. Now it allows the fog lights to run with the corners only.

sideshot.jpg


fog-light-mod.jpg
 

DSG2003Mach1

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It doesnt start paying attention to the O2 sensors until it goes open loop (I forget what coolant temp that occurs) . Im not sure how much of open or closed loop idle is from learned data, disconnecting the battery and turning the lights on for a minute should clear most of that. If you do that I believe they say to let it idle with the AC off for at least 5-10 minutes then turn the AC on and let it idle another 5-10.
 

01silverstang

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It doesnt start paying attention to the O2 sensors until it goes open loop (I forget what coolant temp that occurs) . Im not sure how much of open or closed loop idle is from learned data, disconnecting the battery and turning the lights on for a minute should clear most of that. If you do that I believe they say to let it idle with the AC off for at least 5-10 minutes then turn the AC on and let it idle another 5-10.

Once I get the TPS reading correct and verify if the sensor is bad, I'll go through the steps you outlined.
 

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