Need Some Assistance w/ Problem

[McCauleyWB]

Short back story:
The car has been running well without issue. I was on the freeway a few days ago when it suddenly started misfiring severely and went completely dead. I managed to coast over 3 lanes of traffic and get safely to the shoulder. When turning the key to on again, the tach started jumping around and made a mechanical whining sound. I was on my way to work and couldn't look at it immediately so I had it towed back to my house. Fortunately, it started right up and I was able to get it in to the garage.

Jumping to today:
I hooked up the Scanmaster and took it out for a test drive. It didn't feel as strong as it should and had a high "choppy idle." The Scanmaster showed codes 16, 36, and 42. I believe a "MAF signal too high" also displayed when keeping a consistent RPM too. 16 and 36 aren't even in the manual for the device and I have no idea what they mean. Code 42 says "EST circuit failure. Bad ignition module. Bad ground." I figured as much with the bad ground and found the threading at the end of the battery cable (ground side) was getting stripped. I made a trip to the junkyard and replaced it with a good one. The car runs better now. It does not break up / die, but doesn't feel right either. It could be mental I suppose. I sometimes have to drive 70 miles a day for work and can't chance another breakdown. Finding it similar to LT1*FUN and Cross' post (in the same thread) a couple threads down, I will likely check out the suggestions already discussed there too. Does anyone know why the Scanmaster would show the first two codes, or what it could mean though?

Thanks.

EDIT: So the first two codes were not in the manual that I received with the unit, but I found a resource online that shows the following:
16 - OptiSpark low resolution pulse not found
36 - OptiSpark high resolution signal faulty
42 - Ignition control circuit, short or grounded

I have gone through a bad Opti twice before, but had entirely different problems at the time. Plus, it most recent Opti is fairly new. I have an inkling something else is wrong. Ideas?

[AChotrod]

Sounds like an opti to me. Sorry

[jaysz2893]

Code 36 is the "Opti Kiss Of Death", had it 2 times in 3 years... found a lot of rust build up when i took em apart..

[Fastbird]

Just a crazy though, but check your primary ground behind the battery. Make sure it's not loose, dirty, corroded, or has PS fluid on it. I've seen that one cause some FUNKY stuff.

[Fastbird]

Code 36 is the "Opti Kiss Of Death", had it 2 times in 3 years... found a lot of rust build up when i took em apart..

36 isn't the important one. 16 is. That's the low resolution pulse that the timing is based off. 36 is the high res pulse that's a redundant signal and not needed. The car will run setting a 36, it will NOT run setting a 16. He's got an intermintent 16 if the car is still running, which may point to things other than the opti.

[jaysz2893]

DOH!! i was just reading my old posts on this subject and as usual , you are correct Sean

<-------so much for my user title

Anyway here is some infor to help redeem my title

stolen from here- (http://chevythunder.com/199295_lt1_trouble_codes.htm)

Code 16- Low resolution pulse (distributor). ECM is not detecting the 4X pulse from distributor. Check wiring connections, especially the pigtail connector from the optispark to main wiring harness. This is the black/red wire that goes to terminal "A" on the pigtail connector. On the 1992-93 ecm, this is wire C5 (green connector). 1994-95 ecm, this is wire B2 (black connector). If wiring checks out, you will have to replace the optical sensor module in the distributor.

Code 36- Distributor ignition system. Faulty high resolution (360X) pulse or multiple low resolution pulses detected. Check pigtail connector from distributor to main harness for any opens or shorts. Verify wiring is okay before replacing distributor.

Code 42- Ignition control circuit (ignition module). Check wiring and connections from ignition module and ecm. Replace module only after verifying wiring and connections are not shorted or open.

[Tarheel'Z']

one more slip up jayz2893 and im officially stripping you of your title!dont let it happen again

[Wooshie]

When you replaced the opti were you changing the harness? I know they can cause problems.

[McCauleyWB]

When you replaced the opti were you changing the harness? I know they can cause problems.

I did not change the Opti harness at the time. I also replaced the water pump, fuel pump, filter, etc when working on it last and did not think to replace the harness. I will look in to it. As I mentioned, I did replace the primary ground at the battery because the threading had begun to strip too. That was a big part of the problem. I'll get back in there and clean everything up to rule it out as an ongoing problem. As Fastbird made mention of, it's the problems other than the Opti that concern me.

Thanks guys!