1991 problems when running

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Mar 1, 2010 | 09:19 AM

355flvette

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Racer

Joined: Dec 2007

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From: Orlando Fl

1991 problems when running

I just picked up a 1991. It will start and idle fine it just doesnt seem to go past 2200 rpm and dies. It has a new computer, new tps. Once it gets up to about 2200 it stumbles and then dies. It has about 43-38 lbs of fuel pressure. It was running like how my 87 did when the maf was bad. However this is a map car. Its not throwing any codes. So my next question is any advice? Also ive been reading up and where can you get a scanner and how do you ohm an injector? Thanks

Mar 1, 2010 | 10:16 AM

Y-ME

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From: Ft Myers Florida

Take a voltage tester, set it to ohms. When cold remove the clip off the injector and touch the two terminals with the tester. Ohms should be about 17ohms. If any injector is off by more than 2. ohms replace. Also test again when engine is hot.

Mar 1, 2010 | 10:20 AM

90EXPVette

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Joined: Aug 1999

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From: Grovetown Georgia

I agree, sounds like mine before I replaced the injectors, besides running rich it ran pretty good until the computer couldn't compensate for them any longer and it wouldn't rev past 3K

Mar 1, 2010 | 01:05 PM

355flvette

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Racer

Joined: Dec 2007

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From: Orlando Fl

i tested them all cold and they were all about 16.2 I couldnt keep it running long enough to get it to hot.

Mar 2, 2010 | 12:06 PM

shiyfire

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From: KY

what about the coolant temp sensor?

Mar 3, 2010 | 12:28 PM

355flvette

Thread Starter

Racer

Joined: Dec 2007

Posts: 271

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From: Orlando Fl

put a new fuel filter in it, hot ohm tested the injectors and they stayed the same if not went up a little bit. Any other suggestions. Ill check the coolant temp sensor. It idles rough and smells rich. The fuel systems bled down about 20lbs in about 20 min. But stayed constant when running.

Last edited by 355flvette; Mar 3, 2010 at 12:41 PM.

Mar 4, 2010 | 08:23 AM

90EXPVette

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From: Grovetown Georgia

Can you drop the exhaust? I am wondering if it could be clogged cats...that's a long shot though.

Mar 4, 2010 | 10:49 AM

engle1147

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From: Tampa Florida

Quote:

Originally Posted by 90EXPVette

Can you drop the exhaust? I am wondering if it could be clogged cats...that's a long shot though.

I think this is worth a look....and it is easy. May want to have someone rev the engine while you check for increasingly positive exaust pressure out the tail pipes at higher RPMs