So, I got the car out today, felt excellant the first few miles. Low RPM stumble was still there. First off, when I started It, it started and ran for a few seconds and then shut off. Hmm...Wierd....Start it, it starts fine. Then, on the way back from the gas station, around 25mph it surged REALLY bad(You could see this surge in the tach, unlike all the other stumbles)...Oh well again...So I pick up my paycheck, start the car, runs for a few seconds, shuts off...Hmmm...Get to my friends house, stay for about 20 minutes and go to start the car, runs for a few seconds then quits. Start it back up, and it barely wants to run. I started to drive away and it made a sound like I had an EXTREMELY lopey cam in it, but wouldnt handle any load. As I pressed on the gas, it would make a bogging/EXTREME cam lope sound, but not go anywhere...Now it wont even run for more than 2 seconds.

The Culprit:
My dad and I think the chip above the coil on the stock unit MAY have been damaged when we changed the coil(by pounding on the rivets with a chisel and hammer, could the shock have damaged the chip? Also, could it be the Hypertech chip? Remember, it ran fine for a while until now...How can I rule out everything else? Is it the opti? I havent run the codes yet, Ill do it tomorrow.

Thanks a lot guys!

 

Map sensor.Also ,check all the wires on the pass side of the manifold-ie-going to the iat,and map sensor.Could be toast.(map sensor is on top of the intake manifold,little black thing).Sometimes the gasket goes south I'm told in the map sensor.Hope this helps.Also check those little tiny hoses on the pass side of the manifold for cracks,as they cook pretty well.Hope this helps.(I use a foot long drill bit to remove the rivits).

 

Did this grow worse after you changed the coil? If so, I would guess it would be the ICM ( 'chip' by the coil). Check your PCM for codes. ICM problems usually show up in a scan if they are toasted.

 

Well, we got code 55 after replacing the ICM....Which is "Running lean, fuel pump may be bad" So we are going to replace the pump. The car runs fine till you shut it off and try and start it again. Then it wont run, so what you have to do is disconnect the battery, and hook it back up and it runs fine until you shut it off the next time. The fuel pump regulator is fine...

 

That could be faulty fuel pump. Have you checked the pressure?

 

Nope, Im doing it after school today. I hope this is the problem, so maybe by replacing the whole system my gas guage will work again!

 

Reading code 55 in my book and it says

Electronic Control Module (ECM) fault or oxygen sensor circuit fault or EGR solenoid #3 failure (3.8L VIN1) or fuel lean monitor (Corvette).You sure you don't have any vacuum leaks?Only tryin to help out.My02

 

Hmm...Wierd. It says fuel lean moniter in my Haynes book...Who knows? Lol...Did a pressure test today, 26 PSI, so its obviously lacking some pressure. Doing a fuel filter install on thursday, and if that doesnt work, fuel pump time!

 

Your right it is fuel lean monitor and the recomendation is to check fuel pressure which you did. If it's not the filter it may be the pump. Pressure should be 41 to 47 psi.