98 trans am not running
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98 trans am not running had the car sitting for 5 years decided to work on it again i put a new fuel pump and and new oil pressure sensor since it was leaking was driving around town until i floored the gas pedal and it choked and didn’t go when i let go of the gas it went
i can’t step on the gas without the car dying turns on but then dies the the check engine said it was a map sensor so i replaced it and still ran the same cleaned the o2 sensor and cats replaced the fuel filter 2 weeks ago and today i checked it but when i took the hose off gas was still coming through the hose and the keys weren’t even in the ignition i seriously don’t know what to do anymore car has 150,000 miles
(sorry if that’s a lot)
i can’t step on the gas without the car dying turns on but then dies the the check engine said it was a map sensor so i replaced it and still ran the same cleaned the o2 sensor and cats replaced the fuel filter 2 weeks ago and today i checked it but when i took the hose off gas was still coming through the hose and the keys weren’t even in the ignition i seriously don’t know what to do anymore car has 150,000 miles
(sorry if that’s a lot)
Last edited by ls1neto_; Jan 12, 2023 at 10:22 PM.
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From: Schiller Park, ILL Member: #317
Have you checked fuel pressure under load? The new pump might be faulty or, if pressure is OK, perhaps the injectors need a bench cleaning (or replacement) after all those miles and then 5 years of sitting.
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From: Schiller Park, ILL Member: #317
I would definitely start with fuel pressure, should be at 60psi (+/- 1-2psi for gauge accuracy) at all times (loaded, unloaded, doesn't matter).
If pressure is good under all conditions, I would probably consider the injectors next. You can use an ohm meter to check across their terminals for resistance, see if any are highly divergent or open.
Do you have any other codes present since the MAP sensor code? Have you looked at LTFT/STFT (Long and Short Term Fuel Trims) for evidence of a lean condition (meaning highly elevated, such as ~ +20-25% on LTFT)? Do you have a scanner that can give you this type of data?
If pressure is good under all conditions, I would probably consider the injectors next. You can use an ohm meter to check across their terminals for resistance, see if any are highly divergent or open.
Do you have any other codes present since the MAP sensor code? Have you looked at LTFT/STFT (Long and Short Term Fuel Trims) for evidence of a lean condition (meaning highly elevated, such as ~ +20-25% on LTFT)? Do you have a scanner that can give you this type of data?
Thread Starter
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I would definitely start with fuel pressure, should be at 60psi (+/- 1-2psi for gauge accuracy) at all times (loaded, unloaded, doesn't matter).
If pressure is good under all conditions, I would probably consider the injectors next. You can use an ohm meter to check across their terminals for resistance, see if any are highly divergent or open.
Do you have any other codes present since the MAP sensor code? Have you looked at LTFT/STFT (Long and Short Term Fuel Trims) for evidence of a lean condition (meaning highly elevated, such as ~ +20-25% on LTFT)? Do you have a scanner that can give you this type of data?
If pressure is good under all conditions, I would probably consider the injectors next. You can use an ohm meter to check across their terminals for resistance, see if any are highly divergent or open.
Do you have any other codes present since the MAP sensor code? Have you looked at LTFT/STFT (Long and Short Term Fuel Trims) for evidence of a lean condition (meaning highly elevated, such as ~ +20-25% on LTFT)? Do you have a scanner that can give you this type of data?
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checked the fuel rail no fuel was coming out so i’m thinking the fuel lines are clogged because when i took the old fuel filter off it was badly clogged up and i put a new one im pretty sure it’s not the fuel pump because fuel was coming out of the fuel hose when ignition was on…thanks for your time
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From: Montgomery (Lake Conroe,) TX north of Houston
Thanks for letting us know. Those clogged injectors would explain why the engine won't stay running. Unfortunately, I don't know anything about whether or not bigger injectors can be used on the stock tune. I wouldn't think so but what do I know? I have to ask; why not get a new set of stock injectors?
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Thanks for letting us know. Those clogged injectors would explain why the engine won't stay running. Unfortunately, I don't know anything about whether or not bigger injectors can be used on the stock tune. I wouldn't think so but what do I know? I have to ask; why not get a new set of stock injectors?
TECH Resident
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From: Montgomery (Lake Conroe,) TX north of Houston
Oh. Ok. That makes sense.
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From: Grand Rapids, Michigan
Hey, I have a set of factory '98 28.8 lb. injectors I can sell you, taken off my '98 Formula. I'm going turbo so I won't need them. You can put pretty much any size injector you want in there, though, with adapters and such. I'm going with 120 lb./hr. myself.
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how much you want for them?
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From: Grand Rapids, Michigan
Sorry, just seeing this. I'd like to hit them with my injector tester to make sure they're still functioning ( haven't been run in quite awhile ), but I'd say $80 shipped. I won't sell non-functioning parts to anyone, so let me verify that they still pulse when commanded.
Thread Starter
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Sorry, just seeing this. I'd like to hit them with my injector tester to make sure they're still functioning ( haven't been run in quite awhile ), but I'd say $80 shipped. I won't sell non-functioning parts to anyone, so let me verify that they still pulse when commanded.