Non Thirdgen; LT1 power loss problems? Bad Optispark? - Third Generation F-Body Message Boards

blue86iroc · 08-21-2002, 09:39 PM

A friend of mine has a 1993 Trans Am with an LT1 engine. He's been experiencing some odd problems... "power loss" is probably the closest explanation. He claims that when he hits the gas, his RPMs increase significantly, and then there's a delay before the transmission engages. I was quick to mention that his tranny might be slipping. Then, he puts it in first gear and floors it from a dead stop -- there is absolutely NO wheelspin (and we were even on a hill!). His car has new tires but they don't grip that good. He also mentioned that occasionally, his car cranks for a while when he tries to start it. The car was already taken to a real good garage and they can't figure out what's wrong; they had it for two full days. We're beginning to think that something may be wrong with his Optispark ignition (something I'm not familiar with). Does this sound correct?

Brett · 08-21-2002, 09:58 PM

Without further symptoms it could be the opti or the tranny.

But given the history of problems with the opti, that would be my guess.

How old is the current one on his car? I put a new one in my RS last fall and it was dead by the spring. But that was due to corrosion.

I'm dealing with a busted tranny on my truck right now so I can say that the symptoms could be either. The Ram idles fine and responds fine to throttle inputs in neutral or park. But when the car is in gear there is no power, bad shifts, no shifts, and other than going at part throttle the truck doesn't move.

But usually when people say they are losing power on an LT1 it is the Opti.

blue86iroc · 08-21-2002, 10:20 PM

I'm not sure how old his Opti is... I took a look at it today and it looked a few years old. How often do these things normally need replaced? Also, is there a way he can switch over to a regular distributor? (I'm guessing 'no' since that engine is pushed so far back underneath the windshield)

His car still shifts very firm when he gives it gas, but it just labors to get up to speed. I'm not sure what RPM it's supposed to upshift at (it's an auto) but it normally does it around 4 grand -- that seems normal. Were the auto trannies computerized back in '93?

Brett · 08-21-2002, 11:04 PM

Pretty sure the '93 trannies were still the same 700R4 NON-electrics but designated the 4L60.

No way to convert distributors. You could with a TPI engine and an LT1 intake, but that is way more work than it merits.

Optis are funny. On performance cars some can only last 20,000 the average numbers I see would be around 60,000 but I know several cars that have been driven over 100,000 and still have the factory one. They didn't run worth a damn, but they still ran.

Replacing an opti is a chore. They suck. And I can't imagine doing it on a 4th gen. They're really not THAT bad, but I always hate having to rip the water pump off to do them. And if you try it, know that you don't need to take the crank hub off. You just need to remove the balancer from the crank hub and rotate the Opti once its loose.

Good luck.

And I would suggest posting this on Camaroz28.com under the LT1 Tech forum......... they'll take care of you.

blue86iroc · 08-22-2002, 08:29 AM

Thanks so much, Brett. My friend will be happy to hear that we've finally identified the root of his problem

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