First bout with down time... what could be wrong?

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Jul 15, 2002 | 02:00 PM

mt_789

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From: Walnut Creek CA

First bout with down time... what could be wrong?

Ok, So one week ago I drove the vette to work and back, purring like a kitten. I went to start it last Tuesday morning, and it would start, but then stalled immediately. I left it alone for a few days, and was out of town over the weekend. I tried to fire it up again last night, and it starts, then dies immediately. If I get on the gas, it will run, but very very rich, with a strong gas smell coming out the exhaust. If I let off the gas, it revs a few times, knocks like crazy then eventually dies.
So at first I thought it was a fuel problem, but now that I am assuming that it is not getting enough air. Which of the wonderful sensors or control modules would be the culprit? I am not a mechanic at all, so I have an appointment at the dreaded dealership tomorrow, but I would feel better if I could point them in the right direction. Any suggestions?

Jul 15, 2002 | 07:57 PM

OnDVirg

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From: San Francisco, CA, USA

Re: First bout with down time... what could be wrong? (mt_789)

Don't know what year you have...but it sounds like what happened to mine when the MAF (Mass Air Flow) sensor went out. The good thing is the test is really easy...unplug it and the problem should go away. If not, it's probably something else :)

Jul 15, 2002 | 08:11 PM

VetteNoob

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From: Kyle TX (Because Mojo Made me fill it in)

Re: First bout with down time... what could be wrong? (mt_789)

Ive got $1 on leaky injectors!

Jul 16, 2002 | 02:02 PM

mt_789

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From: Walnut Creek CA

Re: First bout with down time... what could be wrong? (OnDVirg)

Its an 88. Thanks for the advice. I was supposed to take it in this morning to have it looked at, but I could not keep it running enough to even get out of the driveway, let alone down the street... I will unplug the MAF tonight and see what happens. Thanks! I was guessing that it was the MAF or one of the other sensors. If not, then I suppose I can look at the injectors next. I guess owning a 14 year old GM product is the best way to teach yourself how to be a mechanic!

Jul 16, 2002 | 02:20 PM

Black87c4

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From: Taxahoma

Re: First bout with down time... what could be wrong? (mt_789)

You'd be lucky to get the car to run at all by unplugging the MAF. Any codes? If you have a 33 or 34 I'd check the relays.

Jul 16, 2002 | 04:51 PM

mt_789

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From: Walnut Creek CA

Re: First bout with down time... what could be wrong? (Black87c4)

Thanks Black87c4. So if I dont have a code reader, am I screwed? If I think it is the MAF and I pull it, then try to start it, what will the ECM do? I know jack about car repair, but I really dont want to have to tow it to a repair shop if it is something I can screw around with and hopefully get lucky... Maybe I should invest in the diagnostic code reader.

Jul 16, 2002 | 05:34 PM

Black87c4

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From: Taxahoma

Re: First bout with down time... what could be wrong? (mt_789)

Take a paper clip or something similiar and ground out the 2 top right pins on the diag port: Key on

aldl connector pins - you will hear the fans come on, leave it connected
FEDCBA
GHJKLM

Connect B and A, the SES light will flash 12, 3 times and then spit out your code if they exist.

as in longer pause between numbers
flash ----flash-flash-------flash----flash-flash------flash----flash-flash
this would be 12 = no revs, car not started

It will then give you your codes, each one at a time flashed 3 times each

If you had a code 34
flash-flash-flash----flash-flash-flash-flash-----2 more times, when the codes are all displayed it will flash 12 at you again and start all over till you remove the wire.

Make sense, alot of people don't know that you can pull the codes from ecm without a scanner for OBD-I cars, you can get more info from this as well.

If you do it let us know what you find, we'll go from there.

Jul 16, 2002 | 05:38 PM

Black87c4

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From: Taxahoma

Re: First bout with down time... what could be wrong? (Black87c4)

To answer the ? on what it will do if you pull the MAF, 86-89 cars will probably not run or run very rough with the MAF out. I think the 85 cars are different and can't speak to the newer c4's that have MAF's. Most MAF problems are actually the 2 relays that are behind the battery (not easy to get to). Usually easier to just replace both because either one can cause this. But with cars and electronics this isn't 100% just a guess.