First symptom - driving home on freeway car vibrated (for a second or so) and felt like I hit 4 or 5 the Botts' dots on the lane markers even though I was in the middle of my lane.

Stopped for an hour at the beach. Car took 3 tries to get it started. Car stalled a block later at a stop sign, restarted right away. Died another block later at the next stop and would not start.

Had it towed home. Will check for codes in the morning.

 

Opti is 10 years old with 52K miles
ICM is 9 years old with 42K miles
Original Coil

 

did u get any codes? What about fuel pressure check? Could be a number of things...mine did exactly same thing as yours a month ago,turned out to be the opti it had oil in it. Hope this helps

 

Hooked up my computer this morning and ran SCAN9495 and no codes. Decided to see if anything would show up while cranking the motor and car fired right up.

I suspect it is my ICM.

 

oh ok I suspect either that or opti.

 

ICM is suspect.….but checking fuel pressure for these kinds of problems to simply rule fueling in/out as a cause before spending any $ on ignition parts is a good idea IMHO

FP gauge, scan ability and a service manual are must haves unless your wallet is thick enough to pay someone to FIO

 

If it won't start again -

With regard to codes, when you try to start it, let it crank for a longer period. The code for loss of low resolution pulse signal from the Opti can set while cranking, but only if the high resolution pulse is present, and only if it is cranked long enough for a specific number of high res pulses to be received.

Watch for movement of the tach needle while cranking.... 200 to 400 RPM, indication Opti pulse

Check for spark, at the coil wire, and several plugs.

Run Shoebox’s procedure to check for the low resolution pulse:

4th Gen LT1 F-body Tech Articles

 

Replaced the ICM - (lifetime warranty part from Auto Zone) . Fired up immediately, drove smooth and strong during test drive . Will commute a couple of times this week just to confirm.