Slick1Hunting

To set the record straight I too replaced my Opti some years ago with an AC Delco provided product and it's been no problem for several years now. My comment about AutoZone offering the distributor was more as a passing comment that came to mind as I was writing. I was actually surprised when our store received the Optispark distributor because I wouldn't have thought there was sufficient demand for them to warrant us carrying them.

I do wonder who makes the distributor for AC Delco or Delphi as again I wouldn't think there is sufficient demand for them to justify manufacturing the distributor. I have been surprised how many of the parts we sell are made by Bosch. I have read that Valeo makes virtually all if not all of the clutch discs for the M6. I recently read a response from someone at Spec saying they take the Valeo clutch and modify it to meet their specifications. In Kentucky most if not all of our gas for auto fuel comes from Marathon Oil, in fact they have been investigated for price gouging by our commonwealth attorney. I've also learned that there are only a few car battery manufacturers. So it makes me wonder just who makes what.

Anyway, to each his or her own.

 

Dan_the_ManZ28

If you try reading the fuel pressures as suggested in response to your question please be sure to let us know the result. If you eventually replace the fuel pump let us know if it fixed the problem or whatever you find that fixed your miss.

Hope you find the solution soon. I know it is a frustration.

 

This may sound dumb, but the cap and rotor are inside the opti distributer? And the coil is separate? Could the coil be the problem?

 

Dan,

The rotor is inside the Optispark distributor. The cap is part of the body of the distributor that can be removed to gain access to the rotor and both the cap and rotor can be replaced, apparently this can be done without removing the distributor from the car. I didn't know that, however, I believe I have read that an unusual tool is needed to remove the screws holding the cap on but it can be done.

Yes, the ignition coil is separate from the distributor. It is mounted on the front of the left head on the engine. It isn't too much trouble to get to and a stock replacement isn't too expensive. For example a stock coil from AutoZone is priced from $32-$35 depending on the warranty. A higher performance coil from Accel is $62. You can probably find them less expensive if you shop around.

In short anything in the fuel or ignition stream can cause problems like you are experiencing.

I'll mention that most major auto parts chains offer a free tool loaning program. At AutoZone it is called Loan-a-tool. Advance has a similar program. The way the program works at AutoZone is you pay for the tool when you rent it. It is a flat charge that is there is no per day or per week charge. You can keep the tool for a while if you need to, generally up to 90 days. It can be returned after 90 days but it is more of a hassle. Anyway you are essentially buying the tool but when you return it in good shape all your money is refunded to you making the rental free. The cost to rent the fuel pressure tester is around $100 plus tax.

Generally once you install an electrical part it cannot be returned, but I know exceptions are sometimes made to this rule.

That being said you may want to replace the ignition coil to see if it will fix the problem but you'll probably be stuck with the coil if it doesn't.

I have a similar problem I am chasing with my '95Z. I'm getting ready to try new plug wires. I've replaced the plugs both of which you've already done.

Sometime look under your hood on a dark night for a visible spark. I know your wires are new but you want to eliminate bad wires again and it's an easy and cheap process to find out.

One poster has said he fixed his problem by replacing the oxygen sensors. There are two on your car, one for each bank of the engine. A simplified explanation is the O2 sensors report the exhaust fuel mixture to the car's computer telling the computer if the mixture is too rich or too lean. The computer then tries to correct the mixture by adjusting fuel flow.

The one thing that hasn't been mentioned is the Ignition Control Module. This is a module activated by the computer to control the ignition coil. It is mounted on the ignition coil assembly. Mine has failed twice before but when it failed it was a hard failure and the car would barely run if it started at all. Some auto parts stores can test the ignition control module you'll have to check with your local stores.

Good luck.

 

The 4 bolts that hold the Opti cap on are E4 (external) Torx head. If you can't find a socket you can use one of the Torx screws from the throttle body top plate as a socket. Wrap the threads in tape, clamp them in a vise grip, and use the head of the screw as a socket.

A good reference:

Corvette Action Center | Tech Center | C4 Corvette Tech Center | C4 Corvette Optispark Dissection and Replacement

 

Harbor Freight has a 6 piece set for a 1/4 drive for $9.

E-Socket Set

 

OK update, I took it to my family mechanic because he said he will hook it up to a scope to see if all the cylinders are firing as they should. This thing was a big old computer but it showed the ac waves. He said it all checked out perfect and that it might be the MAS. He said to disconnect it and see how it runs and then clean it and see how it runs. Both didn't do a thing. He said its not the opti distributer because it checked out ok on the scope. I Dont wanna have him keep lookin at it because he will charge me. I'm more lost then ever.

 

I assume your "MAS" is really the "MAF".

You mentioned that if it runs for more than 5 minutes that the battery dies.....do you have to recharge it with a battery charger? If that is the case, you have a serious current draw issue or the battery/alternator is bad.

What is the battery voltage when running? Low voltage could cause all kinds of problems.

If the scope showed no electrical signals missing, then you have a fuel or mechanical issue.

If it's consistently missing at idle, it should be easy for a good automotive tech to find the problem.