Hey fellas, I'm still trying to figure out my multiple random misfire (code 0300) on my 96Z28.
Basically, I have brand new as delco opti, plug wires, plugs, and coil. I had my icm checked and its good. My fuel pressure checks out good and so does my compression. basically, I'm getting spark to my cylinders and fuel but timing seems off by a few degrees. But on my pin-type opti, it's not possible to be out of time unless it's 120 degrees at a time and everything mounted flush when we installed the opti so I'm almost 100% sure it's installed correctly.

My question is this,
If i put my engine on top dead center#1 and my rotor button is at 6 oclock does that also mean that the optical sensor(cam sensor) is on the right slot or dash on that cirlce thing.It kinda looks like a small disk that the opti sensor reads.

I'm just ryin to figure out how my car coulld be a couple degrees out of time. It will ccrank up, if you hold it to the floor, and it will idle, very rough but it will idle, but when you try to rev it up you can only get it about 4000rpms. when it finally stalls , after 5 or ten minutes, i guess when it starts in open loop, it will blow back through the throttle body, which suggests to me it is firing on the exhaust stroke instead of the intake stroke. But it's skipping the whole time it's running.

Any suggestions would be greatly appreciated. This problem has been going for about a month now and i would really love to get this car running.

 

Any other codes besides p0300?

If you mount it correctly, timing can't be off, unless the chain or gear is oriented incorrectly. But you said that the rotor was pointing in the six o'clock direction, according to the pic below, it seems correct.
http://shbox.com/1/opti_cyl.jpg

You might try looking to see if you have any fouled plugs or leaky/dirty injectors. Are your injectors getting proper voltage? Is your pcm functioning properly to ground them?

 

Did you verify the plug wires are in the correct order?

 

Yes, I double checked my plug wires and they are in correct order. I don't beleive my plugs are fouled, because i put another new set in to make sure. I may have a pcm problem, but it will run, rpugh, but it will run and i thought i should be getting more codes if any other components were bad. but like i said the only code is an 0300.

 

I was just wondering if it was maybe that metal disk that the opti sensor reads. I was wondering if it could be put on backwards, it's got two screws and a pin so in theory it may can go on upside down and flipped over, Would that make it be a few degrees off time?

 

Putting the Opti optical disc on upside down would really screw things up, since it would reverse the order of the low resolution variable length slots, and those slots are the only thing that tells the PCM which cylinder is approaching TDC. But then, why would you even remove the disc?

 

Injuneer,
I didn't take off the disc. My "mechanic" did, but i don't know why. I was just over there checking things out and he picked it up and showed it to me. That's the only reason i know it was off. I bet he didn't put it back on right and that's my whole problem.

 

If the opti need to be completely torn down like that, there's no point in putting it back in, you should have gotten a new one.