morjackson

Her's my situation. I have a 91 Lumina Euro 3.1 with 109,000 miles. It runs great when it starts.
I have to give it a very small shot of starting fluid (just a few drops actually) and it starts and keeps running every time I do that.
Fuel rail pressure is right at 37 PSI.
Per today's investigationg, the injectors are not firing at starting.
Any ideas are appreciated and welcome.
Thanks,
MJ

maxwedge

This is usually an issue with the crank sensor or ign module or wiring from the cps to the icm, it would also not have spark. Info on crank sensor can be found at autozone.com, repair info section. The icm can be tested at AZ also.

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morjackson

I am getting spark.

maxwedge

Spark and no injector pulse unusual, checked all the fuses of course, got 12v on the pink wire to the icm?

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morjackson

BTW, thanks for replying I appreciate the help. Yep, the fuses are good and the wire to the ICM is sending 12 volts. Talk about confusin!

maxwedge

You need to look for cranking rpms on a scanner when you have no pulse, this points to the icm or cps, or wiring, also try tapping firmly on the pcm, they have been know to fail in the same way. Repeating my self, huh?

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snapperspy040

you might try changing your ignition module it sounds as if you are not getting start pulse from it also it is hard to get to but the crankshaft sensor may also be failing . remove it from the engine and ohm it out with a good quality meter and see how it reads . hope this helps you out. thanks andrew

richtazz

Also check to see if you have fuel pump prime when you first turn the key. The fuel pump relay contacts could be getting sticky, and it's not energizing the fuel pump at initial start up.

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Would you drive any better with that cell phone up your ...?!

morjackson

Thanks Andrew, ICM's cost about $150. Ouch, but that's still better than $1,600 parked in the driveway. LOL
Funny thing is once the car starts it runs great. Some times it needs a shot of starting fluid and other times it doesn't. I had to give it two shots today but started it about six times total so far. I do suspect a contact or connection somewhere.
Any suggestions for an easily digestible manual?

morjackson

I wondered about the pump but if the pump were bad, wouldn't it not run no matter what?

richtazz

not if it's a sticking/faulty relay. The fuel pump relay has two energizing circuits. The first is controlled by the ignition switch during start-up. Once the ECM senses crank sensor signal, the ecm switches control of the relay through the oil pressure switch.

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Would you drive any better with that cell phone up your ...?!

morjackson

I've kind of wondered about the fuel pump. In the past and on different cars, if I listened, I could hear the fuel pump activating. I don't hear it on this car but, then again, I'm 20 years older and don't hear like I used to.