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Some help needed please.

2K views 15 replies 10 participants last post by  j cat 
#1 ·
Today I was driving on the freeway, honestly driving with the flow of traffic. Sped up to over take 2 semi truck. My gauges light up and my engine died. I had to Cousteau to the shoulder. Low oil pressure and chech gauges light stay on. Now the car won't start. Pump primes fine when I open up the switch, engine turns but won't fire. Bad opti, fuel pump, oil pump any suggestions?
 
#2 ·
Check engine light? Any codes to read?
 
#3 · (Edited)
To start with, the CEL and oil pressure light will come on any time the engine quits, or does not start. So will some other lights. The corresponding gauge(s) will read "0".


The correct sequence of events is: the engine died, then the lights lit up.

Since your pump runs for prime, it is probably not the pump. You will have to pull the codes before doing any diagnostic reasoning. It may be something simple, but you need to supply enough information about the problem for someone here to help you.

With enough information, you can get a good starting point for finding the wayward part or parts. With what information you have provided, you can pick any random part, and just replace it. You should expect it to be a part that affects it globally, and I would suspect something electronic, or electrical, because the engine shut down in an instant, without any run-on, or sputtering.

When you have some information of value, post it, and someone may be able to give you guidance.
 
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#4 ·
I recall EXACTLY the same symptoms as posted when I ran out of gas. I also had the SS flatline once (and only once in its entire life) on the interstate. I coasted to a truckstop and let it sit 10 minutes just looking under the hood and it started and ran perfectly ever since. The only code read, "Random misfire".

I believe there are some fluid level sensors that'll keep the car from running. Check your dipstick. Are you getting spark? Have you searched on here or googled, "Car won't start"? As mentioned, post what diagnostics you have, and are, performing. Without replacing a bunch of parts.
 
#5 ·
As Fred mentioned, do some more testing yourself so you can share with us some more details of what you find. Check the stickies for a Very good thread on troubleshooting a "no start" condition. It will walk you thru the systematic process of checking items til you can narrow this down. Once you do, check back and let us know what you found.
 
#6 ·
No codes pop up on scanner. I was checking my oil pressure sensor on the rear of the block next to the egr valve, and only saw 1 wire in the connected and the sensor it self has 3 clips. Is this normal? I had a friend switch the sensor out a while back when I had thrown out my back and could not do it my self. I also tested for spark on cylinder 1 and 3 and got no spark. I am going back to my work place tomorrow with a multi meter to test fuses and check for voltage to coil and resistance on crankshaft sensor.
 
#7 ·
The sensor for your car should have one wire.


If you got no spark, it may be the ignition module, or the grounds at the ignition module . Check, and clean the grounds first.
 
#9 ·
Ok guys. Just walked 9 miles back home from were I have that car parked. I performed all test that were showed in the Opti service video that one of the fellow members posted. Every thing checked out good as the results in the video the only thing that I had to do different was that I was testing on the ignition test connection next to the intake manifold not the actual connector to the opti it self like in the video. I could not get my hand behind the water pump to disconnect it and did not want to brake the connector like I have don't with other connectors in the past that I have had to replace. Every thing checked out like I mention with the exception of not getting any spark at the plugs. All fuses were checked as well. I am leaning towards a bad opti but do you guys know of other things I can check before I order the ACdelco unit for 400 bucks.
 
#13 ·
Another thought in addition to the coil/icm info provided.....

There have been quite a few instances of a bad Opti Harness causing issues. This is the electrical harness that runs from the opti up to the plug on the pass side manifold. If possible, get another to try and swap on there and be sure to inspect the pins and all for solid connections.
 
#10 · (Edited)
#12 ·
I agree. In addition to testing the coil, I would also check the ICM. I think one of these is probably the culprit. if you replace the ICM, be sure to use heat sink paste as it is absolutely necessary. Good luck!
 
#16 ·
very possible the opti rotor fell off since some are not locked in place on the screws with lock tight.

on the opti connector it can be removed if you use a piece of wire that has a 90deg bend to it . a stiff steel wire . the bend will lift the lock and as you pull upward slowly it will release.

ICM can be tested with a tester at some auto part stores. if the ICM is bad replace the coil as a set because a bad coil can and will kill the ICM.

replacing the coil is not easy since if its OEM GM the rivets need to be cut off. I used a cutoff wheel .
 
#15 ·
I feel like an Opti would have given you more symptoms. I feel like that is not going to fix your problems. I just have a feeling though. Is the wire running from the coil to the Opti in good shape as well? Struggling with the idea that opti just 'died' instantaneously.

Good luck. Ill see if I can pull any other ideas out of my ass.
 
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