I just put another LT1 on my 86 Trans Am, but this time I kept it fuel injected. I currently have a 4l60e out of an LS1 car, and my car has been driving perfect until I changed the water pump and the Opti Spark. Put the new water pump in and put in a new cap and rotor. Worked perfect until I pressure washed the engine. I took the car to "dry" off and then it started to miss really bad. Took the water pump and the cap and rotor back off and it had water in it, water came in through the Opti connector at the top of the cap (1995 model vented Opti)the rubber seal was rotten. I blew the cap and rotor and relucter wheel with an air compressor, and reinstalled it back on the car, now it idles perfect ONLY when its cold, but once it warms up it starts to sound like a misfire through the exhaust and if I floor the gas pedal while it's idling the car will completely bog like there's no more spark or it completely flooded if I slowly give it gas until it's floored it will rev all the way to the rev limiter @ 6750rpm. My question is do you think it's my Opti Spark Cap and rotor? I already replaced the Ignition Module ($104 dollars), the Coil, the MAP sensor, and TPS sensor.
Thanks,

Airick,,,,,,,,,

 

As an owner also of a 95Z (LT1) you must understand that you never pressure wash the engine. Yes, your opti is gone. This past spring I had another NAPA waterpump go bad. One of the press fit pipes popped off and soaked underneath the hood and buh bye optispark. Sure, NAPA warranted the waterpump but I ate the $300 optispark and then, it took me 3 Delco optisparks to finally get a good one. Be sure to open up the new unit and tighten the rotor. Quality control is a thing of the past and don't assume because it's a 'Genuine GM' part that it's any good. FWIW, prior to the soaking from the waterpump I was running a Summit Racing branded optispark and it worked fine.

 

So does this mean that it's my whole distributor (Distributor/cap/rotor) or just my cap and rotor? I called Oreilly Auto Parts and the told me that I can bring in my defective AC Delco Cap and Rotor in for a warranty exchange.

Thanks,
Airick......

 

rarely is the cap and rotor a fix. If somehow the cap gets cracked and water intrudes, it's the optical portion that goes bad.

Oh the joys of mounting an expensive distributor behind the waterpump and in front of the engine.

You need the entire $300 unit. I suggest shopping around, try an Accel or Summit brand, don't bother over-paying for the MSD unit and be weary of the $99 units. You can find a genuine GM one for under $350 if you shop around

 

make sure you seal it good when you put the new one on. i used RTV around the cap where it meets the Dis. and dielectric grease on the o-ring and all plug wires. make sure to keep the vent line in good shape.

 

Thanks, I just purchased one from summit, its an accel 59125 distributor complete for 282.90 with shipping,
I hope this takes care of the problem. Now I just can 't get my cooling fans to come on, They come on at low speed with the AC on, but when I turn it off(a/c) the fans turn off as well, i was told that since this motor and Computer came from a 1995 with the OBD1 that the fans kick on at 237 degrees. I let it go a little past that and turned off the engine, that's too damn hot for me. I crossed the number 5 and 6 pin on the OBDI connector with the ignition on to see if the fans come on and they do kick on. I have the Brand new sensor on the water pump and the driver side head, plus bought the 3 relays brand new for the Cooling Fan1, Cooling Fan2, and Cooling Fan3. and still no fans turn on.

Thanks for the help,
Airick

 

the primary fan kicks on at 226. the secondary kicks on at 235. a manual switch or tuning can kick it on earlier. switch thermostats if you decide to have it tuned to turn on earlier.

 

Well my Accel Distributor finally came in and that was the problem, not to mention that when I turn the old distributors rotor by hand from the back side you can hear the bearing and theres a little resistance, but on the Accel piece it turns so easy with no noise and no resistance.

Now I have no more misfire at idle when the cars warm.
Thanks guys,
Airick....

 

good to hear. enjoy!