Need LT1 Specialist in VA

[RKHiPerformance]

My Dad owns a well-maintained 1996 Z28 and is having problems with the car not starting when the outside air is damp or after a rain storm. The engine just spins and doesn't even sputter. We have fuel pressure and the pump primes as expected so the problem seems to be somewhere in the ignition system. When it's dry outside the car starts and runs perfectly.

We replaced the Opti unit and Opti harness, the ignition coil, the control module, and the PCM over the last several weeks with no change. We're running out of ideas and need the help of someone familiar with these cars.

Can anyone recommend a shop in middle or northern VA?

Thanks for any help,
Rick

 

[jwillettgn]

Not in VA. but close, Tick Performance Automotive - Services and Pricing
The only ones we trust with our cars.
I would give them a call and see if they can help.

Good Luck,
Jim

 

[turbofish38]

Double check the vent on the optispark. Something is allowing moisture into the system OR maybe something is wrong with the PASSKEY system. Its kind of strange that it just cranks with a hint of moisture.

 

[chevyII]

replace the cap and rotor on the front of the motor. Its fairly easy but will need a inverted torx socket in the size E4.
Get a GM parts to replace them. My past has shown that usually there is backfireing issuse at the same time from the cabon tracking inside.

 

[RKHiPerformance]

The cap and rotor are both new...The complete Opti assembly was replaced twice in the past few months with no change to the problem.
:frown:

How can I troubleshoot the PASSKEY system?

 

[turbofish38]

I doubt its in the opti. My experience with them is that when they crap out they do it suddenly. No intermittent problems. Maybe its coil related although you said you replaced it. I've heard that coils are marginal on the LT1 just like the TR. I dont know. Maybe the trick of inverting the coil up side down might help. As far as the passkey you'd have to look in a shop manual. The only reason I mentioned it is because I sell a lot of lock cylinders for that system. There are two little wires and they like to break. Its just strange that it wont start if its humid.


BTW the opti on my RMW is going on 300K miles. I wish I could say the same about the water pump.

 

[RKHiPerformance]

We replaced the coil twice, the first time using a parts store replacement and the second time using an AC Delco unit. In both cases, the car failed to start the next time the air was damp or it rained.
Sometimes later in the day, as the air begins to dry, the car will spin, sputter and ultimately catch, although it runs roughly. After a few seconds it clears up and idles normally. Could the PASSKEY cause this behavior?

Thanks again,
Rick

 

[chevyII]

no the pass key is either an no crank or intermintent no crank. Is the throtle body bore clean? only thing I could tell you is get out the hose and spray her down.

 

[machinegun]

Here is what I would do.

1 get the car to the point where the problem occurs. IE give it a bath or spray under the hood with a hose until the issue starts.

Get a code scanner and see if there is anything in the ECM or if the ECM comes alive.

Get a noid light and plug it into one of the injector plugs and see if you get an injector pulse.

Check to see if you are getting fire.

Let me know on any of these and I will see if I can help you but we need these answers.

Also one more thing. Even though you here the pump running please put n a fuel pressure gauge.

Let me know what you get.

 

[chevyII]

try tapping on the tops of the relays/ espeically the fuel pump relay. you can use a screw driver holding the shaft.