1991 trans am sometimes won't start and engine light is on
#1
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Car: 91 Trans Am 'vert
Engine: LB9
Transmission: T5
Axle/Gears: 3.45 9 bolt
1991 trans am sometimes won't start and engine light is on
Hey guys... well I finally bought my third gen (trailered her home on Saturday). It's a 1991 Trans Am convertible with the 305 TPI engine and the 700r4 transmission (4 speed auto). I got a good deal on it ($2800) so I went for it, especially considering that they only made 555 of 'em. Anyway, so this car seems to be kinda dependible so far, however sometimes it won't start. It sounds like it wants to usually (farting/popping while turning over), but I have to let it sit for a minute and then it'll start. It'll start when warm, so I doubt that the engine needs a rebuild (98,000 original miles). And after it does start and idles for about 5 seconds, the "service engine soon" light comes on. It also vibrates pretty hard while idling, it has a consistent idle however it vibrates pretty hard. So what could it be? And approximatley how much to fix?
EDIT: Oh and sometimes it'll fire up instantly and sometimes it takes a little longer with it making the popping (like its about to start) sounds and it'll start after a few seconds of cranking.
EDIT: Oh and sometimes it'll fire up instantly and sometimes it takes a little longer with it making the popping (like its about to start) sounds and it'll start after a few seconds of cranking.
Last edited by musclecar70sfan; 08-09-2009 at 08:00 PM.
#2
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Car: 91 Trans Am 'vert
Engine: LB9
Transmission: T5
Axle/Gears: 3.45 9 bolt
Re: 1991 trans am sometimes won't start and engine light is on
I have some pictures here if it makes a difference.
http://s422.photobucket.com/albums/pp308/pswanney/car/
http://s422.photobucket.com/albums/pp308/pswanney/car/
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Car: 82 S10, 83 280ZX, 84 Z28
Engine: 355 smallblocks..na, 2.8 turbo
Transmission: 85:th350, 84:700R4
Axle/Gears: 85:ford9 4.85, 84:stock 3.24
Re: 1991 trans am sometimes won't start and engine light is on
may just need a tune up. need that code if the ses light is coming on
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Car: 91 Trans Am 'vert
Engine: LB9
Transmission: T5
Axle/Gears: 3.45 9 bolt
Re: 1991 trans am sometimes won't start and engine light is on
That's what I thought. Any other ideas?
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Car: 91 Trans Am 'vert
Engine: LB9
Transmission: T5
Axle/Gears: 3.45 9 bolt
Re: 1991 trans am sometimes won't start and engine light is on
I had my mechanic look at it today and he found that 1 cylinder wasn't firing so it's running on 7 now. He said it could be bad plug, wire, or injector.
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Car: 1992 RS
Engine: Carbed 350
Transmission: 700R4
Axle/Gears: 3.42 posi
Re: 1991 trans am sometimes won't start and engine light is on
1st, make sure the plug wire is all the way on the plug and staying there. 2nd, check the continuity of the plug wires - even brand new wires are bad in the box. 3rd, get that cose from the ECM - use a paperclip and read the tech article on getting codes.
I'm guesing you have a vacuum leak - they generally make a rough shaking idle. But 1st, get that #1 plug firing and check those codes.
I'm guesing you have a vacuum leak - they generally make a rough shaking idle. But 1st, get that #1 plug firing and check those codes.
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Car: 91 Trans Am 'vert
Engine: LB9
Transmission: T5
Axle/Gears: 3.45 9 bolt
Re: 1991 trans am sometimes won't start and engine light is on
Thanks, I'll be looking at it tomorrow. The mechanic probably knows more than I do but the hard restarts may be due to a short in the fuel injection (according to him) since that one cylinder might not be firing due to a bad injector. However he also told me that I should check the oil and sniff it to see if it smells like gas. If it does, that means the injector IS working and is just dumping gas into the cylinder without the plug igniting it... which would mean that the plug/wire is bad. But the oil does smell like gas. Hmmmm. So can the injector be squirting gas and shorting out? I'll first check the plug/wire out then I'll call him and let you guys know.
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