I have been having his problem and need some ideas what to look for. When I really get on it and go WOT and hit the higher rpm's the car will cut out for a split second. I can drive it for weeks and have no problems and it is running awesome. Its like the ignition will shut off for 1/10 of a second and I can get right back on it. I checked the fuel pressure and its fine and never drops. If I go 90% throttle and be a little careful it will never have a problem. Any ideas would be greatly appreciated!

 

hmmmm. Have you driven around with a pressure gauge hooked up to the car? What psi are you getting at WOT? When is the last time you did plugs and wires? Did you visually inspect wires from below and above wherever you can see? What rpm does PCMFORLESS have you shifting at? Is it over stock? On the dyno at times my car broke up slightly in the very high rpm and It was due to a failing plug. Thats about all Ive got boss.

 

The fuel pressure is fine. It stays where it should and when I drive with the fuel pressure gauge on the windshield, there is no issues. New plugs and wires. The shift points seems high, but not sure exactly where it is set at. I have wondered if it could be hitting the rev limiter, but have no idea what that feels like. Anyone know how to describe what you notice when it happens?

 

I had a very similar issue that turned out to be the opti, no codes, but when I removed the opti, the bearing inside the opti was allowing too much lateral movement. It only caused problems at very high rpms.

 

The opti is pretty new, so it wouldn't be worn out.

 

My ac delco opti had around 20000 on it when this happened.

 

You are are hitting the rev limiter as described in your first post.

 

I checked and the rpm's are between 5500 and 6000 when it happens. Its not the easiest thing to see exactly because you are really moving and it doesn't happen all the time. It mostly happens when I stomp on it and it down shifts and revs quickly. It will only happen when shifting into second, I assume because that is the only time the cars hits that high of a rpm. I wonder because the car shifts normal and at the right rpm on regular driving, if retuning it and lowering the shift point will fix the problem.