1992 Supra Mariah Power Tec Idle Problem

[100Million]

I have a 1992 Supra Mariah Powertec 351 Windsor. I'm trying to figure out how to make it idle properly.

What my problem is, is that when I put it in gear I lose about 500 RPM's. I'm under the impression that you're only supposed to lose about 100 RPM's.

I have replaced all my plug wires and my plugs and fuel filter. There is not much else to replace.

What happens when I put it in the forward gear or the reverse gear the engine starts stumbling and I have to give it more gas to keep it running.

I was wondering if someone could help me out and direct me in the right direction of what might be causing this problem.

The only way I can keep the engine from stumbling and running is to turn the RPMS up via the idle screw.

Besides that the boat runs GREAT all all Speeds and Idle...

Any help would be appreciated.

Thanks

Chris Richer

Bend, ORegon

https://forum.supraboats.com/showthread.php?21062-92-Mariah-Carb-Adjustments&highlight=Power+Tec+Idle

This Guy has the same problem I have hehe

[100Million]

Ideas

https://forum.supraboats.com/showthread.php?15163-92-Sunsport-PCM-351-will-die-at-idle-and-have-to-give-it-extra-throttle-in-quot-gear-quot/page2

[michael hunter]

You probably have a Pro Tech system. There are no more parts available anymore. Your best solution is to convert it to a DUI [Davis Unified Ignition] system very simple unless you have fuel injection.