Car barely runs after headers
#1
Car barely runs after headers
I have a 1985 trans am with the 305 TPI and I recently put a set of headers on it and removed the smog pump, A/C, and cat (So the car is currently running open headers). After all was said and done I started the car which was no problem but right when I put it into drive and gave it any gas the car would almost die and then barely come back to life when its driving. The car idles fine but whenever it gets gas it almost dies. My dad thinks that their is an EGR valve line that needs to plugged but I haven't been able to find any information. I have also not had the air box on the car while it has run. I need to know if the problem is an issue with the EGR valve or if its because the car currently has no back pressure and no air filter. I appreciate your time.
#2
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Car: 1987 SC/1985 TA
Engine: 350/vortec/fitech
Transmission: T56
Axle/Gears: 3.27 9-bolt
Re: Car barely runs after headers
O2 sensor is going to be super confused with open headers.
#4
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Car: 87 GTA, 88 GTA, 92 TA, 72 RS SS
Engine: 350, 350, 305, 396
Transmission: T56, 700r4, 700r4, T56
Axle/Gears: 3.42, 3.23, 3.23, 3.73
Re: Car barely runs after headers
The o2 sensor shouldn't cause the issue you are having, go back through and check all the connections you unplugged to put the headers on. Sounds like the MAF is unplugged based on your problem description.
#5
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Re: Car barely runs after headers
try adding at least 18"-24" of exhaust pipe after the collectors.
i have an air fuel ratio gauge in my car, using the O2 sensor. if i run open headers, it reads noticeably leaner. could be your issue?
i have an air fuel ratio gauge in my car, using the O2 sensor. if i run open headers, it reads noticeably leaner. could be your issue?
#6
Re: Car barely runs after headers
Thanks for all the suggestions, I'm currently waiting on a little bit nicer weather so I can put the car on my outside lift and fit the rest of the exhaust and I hope that solves my problems.
#7
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Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Car barely runs after headers
Check your spark plug wires. When I did my first header swap almost a decade ago (wow time flys) I was having weird problems too a couple days after. Turned out to be two spark plug cables got fried and was causing all kinds of mess.
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#9
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Car: 1991 Z28
Engine: L31-R 350 w/ EBL P4
Transmission: 700R4
Axle/Gears: 2.73
Re: Car barely runs after headers
It sounds like all he is doing is starting the car, putting it into drive, and then trying to keep it running without driving it anyway. If that is the case, then his car will still be in open loop and will be ignoring the O2 sensor readings. Something other than the O2 sensor is causing this issue.
#10
Re: Car barely runs after headers
Thanks for all of your help and suggestions but in the end it ended up being that the MAF sensor wasn't even on the car because I had no air box on it when I ran the car (Yes I feel stupid)