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Newbie needs some help on a 98 Grand Prix

goatmanjohn

New member
Hi everyone, i'm new here and excited to be a part of the forum. I hope one of you fine gents or ladies can help me out with my daughters Grand Prix. She went to get in it this morning and it wouldn't start. The fuel pump is working so i pulled a sparkplug out, grounded it and there was no spark. I asked her if it was acting up lately and she did say it was getting harder to start and it would kinda jerk at times. Where would be a good place to start checking for this problem. I'm old school and don't know a lot about all these sensors and computers they have in these newer cars. Would a crankshaft or camshaft sensor cause this or could it be the computer module. Any help would be appreciated.......anyway i'm glad to be aboard.
 


Would a crankshaft or camshaft sensor cause this or could it be the computer module. Any help would be appreciated.......anyway i'm glad to be aboard.

Possibly. If you can see if the car has any codes that would be ideal. I understand it is not running so that may be an issue.


It could also be the ICM (ignition control module) which is located under the coil packs.
 
No problem. That sounds like a vacume leak. Wich is not the cause of you're spark issue but also needs to be addressed

I wish I could recomed a way to test all of this stuff but i'm not sure how. Let me look in the GM service manual and i'll get back to ya.
 
Thanks TDCRacing, i'd really appreciate that. Well i decided to start with the three ignition coil packs. I pulled the 14 terminal connector off and with the ignition turned in the on position i tested each terminal with my voltmeter. I found only one terminal that read 12 volts....actually 11.67 volts to be exact. Can you tell me if one terminal feeds all three ignition coils. After that i decided to check each spark plug for spark and none of them had any.
 
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I've had the same problem with P0171. I've replaced both O2 sensors and the Mass Air Flow sensor. The car was even in a garage and they could not figure it out. They did check for vacuum leaks and found none. I am at a loss as I need to go through emissions.
 


Hi, i think i might be closing in on this pain in the a#@ spark problem of mine. I've got power to the ignition module and to the primary side of each coil but theres no voltage coming out of any of the three coils secondary terminals ...so please correct me im wrong in thinking the problem lies within the ignition module. Just to make sure (cause these babies aren't cheap) can these modules be bench tested...if so how or by whom. Thanks in advance for all the help guys. i really appreciate it.
 
auto zone can test the icm an the crank position sensor when my cps went out my tach would quit working randomly while driving u need to check to see if the icm is getting siginal from cps
 


my cps is the one that came on my new block with only 26k miles on it, do u think it can be already broken, or maybe since the wires going to it got cut on the accessory belt it could have shorted something out and fried something?
 
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