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97 grand prix troubles and iam stumped

Posted: Thu Mar 15, 2012 12:43 am
by razmatazz
ok so i recently picked up a 97 grand prix se and have noticed a problem that shows it ugly face at random times.

so ill do my best to explain it. but kind of hard to with out personally experiencing it.

Here is what happens
Ill be driving down the road doesnt matter the speed. It will be cruising just find then randomly it will feel like the engine trys to shut off. what i mean by that is that i loose my power steering and brakes and the rpm's will drop. Then after that all happens a split second later the rpm's go back to there correct spot i get all my power steering and brakes back. When it does the semi shut off the car will shake like it would when you start it. those symptoms lead me to believe that it is trying to shut down. i am 99% sure its not tranny related due to the fact that the rpms drop instead of jump, and the fact that i loose power. dont think its battery related cause the dash lights dont flicker and my stereo does not get effected. i dont believe its the fuel pump cause every time the key turns you hear the pump "prime" and that there is a constant flow of fuel. so it leads me to believe that its something oil related. my car doesnt burn or leak any. i dont have any low pressure light on or oil lights. so it leads me to believe that the oil pressure sending unit it the culprit. sadly the grand prix doesnt have an oil pressure gauge for me to look at when it happens. ive seen multiply postings on this site relating do oil pressure switches.

any ideas if i am right or wrong? let me know. like i said its hard to explain and sorry if the description doesnt help much.

Thanks

Re: 97 grand prix troubles and iam stumped

Posted: Thu Mar 15, 2012 7:00 am
by razmatazz
thought i should add the bit that just recently happened. i was driving on some back road and come to a stop sign. i turned right i drove maybe a 100 feet when the car did a hick up (the term ill use for almost shutting down the regaining its power) the did another maybe 15 feet later and shut off... it didnt start back up right away. although i did not turn the key all the way back to lock. but it took me turning the key and pumping the gas pedal a little to get it going again... so i guess iam back to the fuel pump.

when i changed the fuel filter two days ago we held the filter vertically so the inlet was pointing downwards. what came out shocked me. the gunk that came out was blacker than black and looked like sludge. so i would guess that a nasty a** filter would add strain to the pump. the car still had the original fuel filter with 158xxx miles on it and so did the air filter which was also blacker than black.

Re: 97 grand prix troubles and iam stumped

Posted: Thu Mar 15, 2012 8:52 am
by razmatazz
It happened again. It hick upped and the battery light came on.

Re: 97 grand prix troubles and iam stumped

Posted: Thu Mar 15, 2012 12:33 pm
by Archon
It could be a few things. Start by checking your fuel pressure. Also, try disconnecting the plug to the MAF sensor, and see if the problem goes away. You could also have an intermittent crankshaft position sensor.

Re: 97 grand prix troubles and iam stumped

Posted: Thu Mar 15, 2012 3:32 pm
by razmatazz
Wouldn't taking off the plug on the maf cause problems?

And how do I go about testing the fuel pressure

Re: 97 grand prix troubles and iam stumped

Posted: Thu Mar 15, 2012 5:25 pm
by 00Beast
It won't idle great, but it will run.

You borrow a fuel pressure tester from a parts store and screw it on the schrader fitting on the fuel rail. You want to test key on engine off, key on engine idling, and key off engine off, watching how fast it bleeds down.

Re: 97 grand prix troubles and iam stumped

Posted: Thu Mar 15, 2012 8:16 pm
by razmatazz
so i was looking through fuses and battery wires and saw this O connecter sitting on a bolt with no nut to hold it in place. it is located in the left side in the middle befor the alternator and right above the belt. any ideal if it is a ground for something?
Image

Re: 97 grand prix troubles and iam stumped

Posted: Fri Mar 16, 2012 12:09 am
by Archon
Looks like one of the under hood grounds that could cause your problems. Generally, it is attached to the same stud that holds the ICM plate to the engine.

Re: 97 grand prix troubles and iam stumped

Posted: Fri Mar 16, 2012 12:22 am
by razmatazz
well got it grounded out. fuel pressure is still good got that checked today. any chance that a bad ECU would cause these problem?

Re: 97 grand prix troubles and iam stumped

Posted: Fri Mar 16, 2012 12:41 pm
by Archon
If you are thinking of the car's computer, it's possible, but wouldn't be toward the top of the list of suspects. They're generally pretty reliable.

Re: 97 grand prix troubles and iam stumped

Posted: Tue Mar 20, 2012 12:18 am
by razmatazz
nother update:

ok so the problem has continued to happen and ive taken a closer look at the gauges when it happens. also sometimes when i go to start it either it being after it kills on me or from starting it in a parking spot. what sometimes happens is that the engine will crank but not turn over. when that happens the oil and battery light will be on. also when cranking the engine i will pump the gas and the engine will turn over then it will chug then kill on me.

hopefully that helps you guys help me a little more.

thanks