91 TPI Z28 Bogging & Rough Idle when Warm
08-06-2011, 10:08 AM
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91 TPI Z28 Bogging & Rough Idle when Warm
Hey guys I'm new to the forum and have a quick question.
I have a 91 TPI Z28 Auto. with 120,000miles headers and full exhaust and egr is eliminated.
When I start the car cold it idles fine but as soon as it gets to operating temp it starts to bog and if I'm in gear it causes the car to hop forwards but if i put it in neutral the idle gets slightly better.
IAC is fine and TB was cleaned as well. Tune was done and only premium fuel is being used.
Any input we be great thanks for the help in advance.
I have a 91 TPI Z28 Auto. with 120,000miles headers and full exhaust and egr is eliminated.
When I start the car cold it idles fine but as soon as it gets to operating temp it starts to bog and if I'm in gear it causes the car to hop forwards but if i put it in neutral the idle gets slightly better.
IAC is fine and TB was cleaned as well. Tune was done and only premium fuel is being used.
Any input we be great thanks for the help in advance.
08-07-2011, 08:37 AM
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: 91 TPI Z28 Bogging & Rough Idle when Warm
Ohm check your injectors
08-07-2011, 08:48 AM
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Re: 91 TPI Z28 Bogging & Rough Idle when Warm
Took it to GM and they checked the injectors. They replaced 2 or 3 i forget now but the problem was still there. I'm also not getting any check engine light codes at all.
08-07-2011, 09:02 AM
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Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: 91 TPI Z28 Bogging & Rough Idle when Warm
can you even get a code 12? that is normal. If your injectors are fine then i would look toward a vacum leak or a bad ecm.Does your car pass the key test? Turn key on and watch for a quick blink , then SES light should turn solid? that should let you know the prom is still good.
08-07-2011, 09:03 AM
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