Engine dies intermittently
 

I think this one may have gotten the better of me.

My problem started a few weeks ago when my motor cut out while driving to work but it caught again within a couple of seconds. It happened again a couple of times coming home from work except it required a restart. So far this problem has not left me stranded.

With the car parked and the keyswitch to on (engine not running) I can get the car to cycle the Air Injection Pump, Fuel Pump and Ignition after the car has been sitting for up to 1/2 hour. This cycling sounds like the ECU initializing and it can occur once, 2-5 times and other times it has cycled repeatedly until I turn off the keyswitch.

When the problem happens with the car running it sets a host of codes:
84 Downshift Fault
83 TCC Control Feedback
16 Low Res Failure
42 EST Grounded
36 Hi Res Failure

I have replaced a few optis in my day and 2 bad coils so some of these codes are familiar but whenever my ignition had died in the past it never recovered, and it never caused my ECU to recycle my air pump and fuel pump repeatedly. I am thinking these codes may be getting set when the ECU cuts power to the ignition when it recycles. Kind of a chicken or the egg kind of thing.

I have a suspicion that my ECU may be ill. Has anyone seen anything like this?

I've had these same conditions twice before, and each time it was the optispark.

Well I guess I'll swap out the Opti and see what happens.

Thanks for the response.

you should check the opti harness and the mating contacts in the distributor, as well as the ones to the engine main harness.

well I was going to start a new thread but it seems like im having the same problem as you. I'm getting the follow codes:

16 lo-res fail
36 hi-res fail
41 est open
48 MAF system fail
51 EPROM/Flash Checksum Fail
84 3-2 Downshift Feedback Fault

Don't hijack others threads. See info on your own thread.

no hijack intended, just stating similar problem with some similar codes.

I will ring through the harness proir to ordering a replacement opti, but this feels like something more than a continuity issue. I have learned from experience that when I change an Opti, I always change the harness between the Opti and the main harness to prevent any corrosion from the old harness from getting on new Opti contacts.

One thing I would like to know is what type of preservative GM used in their Production Opti Connections. My original Opti I had over 90,000 mile on it and when it failed. I disconnected the original Opti harness it was packed with some type of clear jelly, almost like a silicone grease. I would really like to use this corrosion preservative on any future Opti harness connections if I could figure out what they were using.

I've seen similar jelly-like packets that they sell at registers at advanced that would probably help out. I believe its called dielectric grease.

wondering
 

wondering if u could send me a pic of the opti spark itself?? berakahs@hotmail.com... i have a similar problem.. frequent stalling

I can send you a picture of the failed unit when its out but if the replacement Opti fixes the problem I will not be opening it up, I will be throwing it out.

I just found out the replacement Ignition harness price went from around $60 when I bought on a couple of years ago to about $180 today. Great.

sweet
 

thx... id appreciate it.. just so i know wat i need...

As far as what you will need:

2 Water Pump Gaskets (already have a few in my tool box from the last time)
The Optispark itself
The Ignition Harness is optional but in my opinion a good idea.

Ok.
 

do have the part number and the round a bout price... and the brand of optispark? thx. just so that i know what it is i need...

I have purchased the last couple of Optisparks from thepartsladi ebay store.

For my harness I went through Jason Cromer.