Well story started when my 94 Camaro threw a high res code from my MSD billet Opti. I replaced my MSD with the original known-good opti that I removed for MSD one and now have a no start issue. I removed that opti and purchased a new one from amazon and installed with no luck. I removed that one and replaced with another one they sent me under warranty and still no start. I didn't force it on and I also checked the position of the double spaced sprocket with a flashlight and mirror before I installed new one. I removed wiring harness and tested continuity between opti and computer, also tested all other sensors for continuity and had no issues with wiring harness. both PCM power feed wires have power and the pcm ground is good. ignition system has power and opti is getting power/ref signal. fuel pressure is a steady 45 and doesn't seem to drop at all during cranking. also no voltage is seen on the white wire going to the ignition module from the computer during cranking. I also noticed when I spun the opti free with it hooked up and power on, the injectors didn't seem to react at all and no change in fuel pressure was noticed. should I just keep replacing opti after opti assuming they just keep sending me bad ones over and over again, or is there something I'm missing. maybe a bad computer??? I just don't want to keep throwing parts at this thing I'm already into the car a new coil, ignition module, and opti. plugs and wires were done before the problem ever started and are maybe a year old. car also has an lt4 hot cam kit, 36lb injectors, and moroso CAI. car started a bit harder after cam install but still ran just fine once it started. I guess I'm stumped at this point. I also do not have an oscilloscope to check opti output. thanks for reading!
-Paul

 

I would check to see if the plugs are fouled. Just pull the easiest one to get to and look at it. If it is wet and smells like gas you will have to put new plugs in the car. Also, I would take the coil wire off the opti and put a screw driver in the plug and hold it against the block to see if you are getting spark from the coil. Have someone crank it over and see if there is any spark. If no spark then your computer is not sending the signal to fire the coil for some reason. It could be a bad PCM but you have to eliminate that through the trouble shooting unless you can swap out a PCM to see if that fixes the issue.

 

Also, if you have a scanner, try hooking up the opti to the scanner and spinning it with the key on with a drill to see what rpm reading you are getting. This sounds like a pcm issue but there are so many other points that can fail and cause this issue.

 

Nostang, the plugs look good and they are dry after crankng. I tried the home made noid light trick with a test light and didn't get anything on the ground side of the injector. also I have no spark when I hold the screw driver with the coil wire attached against the block. all signs are pointed to opti according to shoebox's site except ive replaced it 3 times. I will have to look into getting a scan tool to read the opti output. would the rpm reading show on the vehicle tach also if I spin opti with drill??

 

Hmmm, I wonder if you are having a VATS issue. Did you look into that as a cause? Are you getting any spark at all?

 

I have VATS turned off with Tunercats right now. Also the security light isn't on during crank. no spark from coil, and no signal sent from computer (white wire) to ICM to tell it to spark. This thing is a PITA

 

Do you have a spare pcm to swap out. I am thinking a PCM. I would not think you could get that many bad optis.

 

I do not have a spare PCM to try. One thing that makes me thing OPTI still is that I do have good reference signal to all sensors including the opti. also power and grounds were all good. I'm thinking of emailing Solomon and see if he can check the computer, and also bite the bullet and get one of those 400 dollar AC delco Opti's. I hope this gets the problem solved. if not I will post again soon. thanks for your help man!
-Paul

 

The problem today is with parts, I know one of people that I’ve had to go through like four opti’s, and coils ect. If all signals point to the OPTi I hate to say it but you might have to try another one

 

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