Is the motor grounded to the frame.

 

A 41 has nothing to do with the opti.

 

Yes.

As a side note to amend something I said earlier, I believe early forms of the hesitation problem surfaced before the computer was moved. It has been ever increasing issue in its severity. I remembered an incident where is jerked a little bit coming from a stop before any changes were made.

 

Looking at the logic diagram for DTC 41 (admittedly for a different year), I don't see any reference to the Opti. It does show that the problem can be caused by a faulty PCM, or a faulty coil.

Even thinking about the Delteq is a serious mistake. The company is out of business, there is no longer any technical support, and no source of replacement parts. It wasn't that great a system anyway.

 

Well, a small update. I replaced the new coil and the ICM with a used pair and now code 41 is gone and the SES light no longer illuminates.

Now for some reason when I scan for codes DTC 83 shows up in the history codes section. As a side note the donor LT1 and 4L60E is from a '94 Z28.

Took it out yesterday and it worked fine. I just got back from a test drive today and 13 minutes in the car began to stumble, bog and even quit. It started today as a little skip then it quickly degraded to only allowing me to apply slight throttle as it jerked around and bucked.

So now I still have the bucking problem and a new code that was not there before, DTC 83. I had code 83 before the test drive today.

 

83 is a trans code

Sounds as though it runs ok until it warms up as in going to closed loop. Pull an O2 connector and force it to stay in open loop and see if it runs ok then. Then you will know if it's a closed loop control problem

 

I pulled the left side O2 sensor connector and let it idle around for about 8 minutes then as I was just moving it around the property it began to stumble and show the same problem.

 

Sounds as though you may have an electrical item breaking down with heat soak. Try heating up one ignition device at a time with a blow dryer while it's dead cold to see how it runs while it's cold.

 

Code 41 or 42 can sometimes accompany 16 and 36 for the opti. Whether a 41 can occur without any opti codes is iffy, but I would not totally dismiss the idea.

 

I have been suspicious of heat soak causing the problem but as of now I have replaced the coil and ICM with a used pair which eliminated code 41. I believe the coil was at fault because I borrowed the ICM from the '94 Z28 and it still had the problem right from the engine start up which counters the heat soak theory. I did end up replacing the optispark with a new GM unit hoping the would fix it which it did not.

All that remains is a bad wire or connection somewhere even though I have tested some of the involved wires, and error in the PCM tune or the fuel pump giving out intermittently.

 

Anyone have any ideas? Please and thank you.

 

What's the fuel pressure doing about the time of the problem?

 

I'm in the process now of getting a fuel pressure instrument to find out if the fuel pump is intermittently failing.

Thank you for you continued help.

 

I got a fuel pressure gauge hooked up but of course I could not induce the problem with the gauge connected. I ended up replacing the fuel pump out of desperation and I took the car out today everything was fine until 12 minutes into the drive the same old problem showed up.

I think the fuel pressure regulator is okay, no fuel in the vacuum tube and when I remove the vacuum tube the fuel pressure jumps up. Could a clogged fuel filter cause this issue? It is new, but so was my coil that was tripping code 41. No new codes have showed up either.

Thanks

 

Let me get this straight. You have a gage, you suspect you have a fuel problem. The problem doesn't occur while the gage is on it. But you put a fuel pump in it any way???????

So before I start pounding my head against the wall, do you plan on leaving the gage on during the problem?