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'03 GT problems.

drivinfast247

New member
Hello all. New to this forum, and I have some questions.

My girlfriends car.

All within the last month car would randomly not want to start. Didn't matter the weather. Was hit or miss if car would start, but once started ran ok. Recently, car would stall while driving. Would have to wait a few minutes and it would start back up and drive fine.

Engine light came on and had code read: Cam position sensor. I went to install that and noticed oil and grunge build-up on top of intake manifold. I'm not new to 3800's and knew that an intake manifold and plenum gasket are needing replaced. Been there before, done them before.

Went ahead and replaced intake and plenum gaskets. Also replaced cam position sensor, followed by a coolant flush and oil change. Car ran great for about 2 days and then stalled again. This time no "check engine" light. Also, sometimes engine would not start after sitting for random amounts of time.

Did a little research and went ahead and replaced the fuel pump relay. Car ran great for 2 days.

Yesterday car started right up, but died after about 30 seconds of idling. Would not start up again.

Checked for spark and fuel pressure and all looked good. I was angry so I walked away from it. Today I go and car fires right up like nothing happened. Check engine light came on, so I went and had the code read again, cam position sensor!!

Car started and ran fine. So I drove it home so I can check the wiring at the cam sensor all looks good. Car started up and idled for about 10 mins without issue. I shut it off to reinstall coolant reservoir. Car will not start!!

Help!!
 


And when I say "will not start" I mean the engine turns over, has fuel pressure and spark.

Almost like injectors are not working.

Is it safe to hook a test light up to an injector plug?

Is it possible to have a "new" bad cam sensor?

Within the last year these are the repairs I've made to this vehicle:

Full brake job
Front wheel bearings
Fuel filter
Ignition control module
Intake gaskets
Plenum gasket
Cam position sensor

Also had a trans rebuild about 2 years ago.

Car has 133k
 
And when I say "will not start" I mean the engine turns over, has fuel pressure and spark.

Almost like injectors are not working.

Is it safe to hook a test light up to an injector plug?

Is it possible to have a "new" bad cam sensor?

Within the last year these are the repairs I've made to this vehicle:

Full brake job
Front wheel bearings
Fuel filter
Ignition control module
Intake gaskets
Plenum gasket
Cam position sensor

Also had a trans rebuild about 2 years ago.

Car has 133k

Try to pull the maf sensor out se if it runs.

Thats what im having right now
 
check the harness to the cam and crank sensors, as well as the icm harness, one plugs into the other.

cam and crank sensor work with the icm to determine when to throw the spark.

may even have a bad crank sensor, as they almost never throw a code.

and this is off the wall but, ever clean the TB? long shot but they will make starting hard sometimes if its got a lot of carbon build up.


and yes you can put a test light into the injector plug to test it. or jam a side marker bulb from the head light in the injector plug, if it flashes, its working. same as the test light, it will flash on and off, rapidly.
 


check the harness to the cam and crank sensors, as well as the icm harness, one plugs into the other.

cam and crank sensor work with the icm to determine when to throw the spark.

may even have a bad crank sensor, as they almost never throw a code.

and this is off the wall but, ever clean the TB? long shot but they will make starting hard sometimes if its got a lot of carbon build up.


and yes you can put a test light into the injector plug to test it. or jam a side marker bulb from the head light in the injector plug, if it flashes, its working. same as the test light, it will flash on and off, rapidly.

I'll check the harness again. I'm getting an OEM cam sensor tomorrow to replace the cheaper one I installed. Thanks!
 
What brand of MAF did you get? The aftermarket ones (Autozone, etc.) are known to have issues. Best to stick w/ a Delco one or find one in the junkyard.
 
I think it was that cheap cam sensor. Put an AC Delco in today and so far so good. Hope that's all it was.

Thanks for the replies! Thanks for your time!
 


You havent replaced the crank sensor yet have you? The one behind the harmonic balancer.

I would do that if you havent, they are known to cause random stalling.
 


Check the Wire to your Alternator to ensure it is Tight. I was having this issue and turned out to be a bad connection to the Alternator. <-- Could have saved my a New Battery if I knew this before I changed it.
 
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