Ok...car is '89 2.5 with enforcer turbo, Daytona VNT intercooler, converted to 5 speed, 3 bar setup with boost at 20 pounds, accufab, FFV injectors, new plugs and somewhat new Magnecors, open downpipe, new (last summer) speed sensor, new cap and rotor, re-timed a hundred times...this is all my "relevant" mods. Car is set to 12 degrees and fuel is set to 55 PSI static pressure. I'd like to test my fuel at the rail, but my gauge leaks like crazy.


Basically, if I hammer the gas in 3rd, 4th or 5th gear, as soon as boost reaches close to 20 pounds, I experience what feels exactly like overboost shut down, which is fuel cut. Moparman and I have been through the cal over and over and made sure overboost was shut off.

When it's cold outside, my car takes FOREVER to come out of cold enrichment and my temp gauge usually stays pretty close to the coldest mark. I assumed that this was causing the problem since Moparman was having a similar problem and his van runs very cold. Also...this overboost thing don't occur 100% of the time and seemed to be absent when my car would warm up from sitting.

That all went out the window when it got over 60 degrees here and my car was at normal temps. I rolled into it in 3rd and experienced the fuel cut problem once again. I mashed it yesterday in 2nd and wound it out...boost was over 15 pounds and I roasted the tires...I experienced no problems.

Moparman also thinks that having less than a quarter tank of gas and having the fuel slosh to the back of the tank would cause this...but my problem isn't consistent with a certain fuel level.

When I switched to a 3 bar cal, I got my map sensor from ebay used for $30 and think that maybe it's not reading correctly. I also think that maybe the fact that I'm running a stock, original fuel pump could be the problem....but it seems that a fuel pump that's not flowing enough fuel will cause the car to sputter and lose power more than an abrupt overboost like situation.

This is just frustrating and every time I think I have it solved, it comes back.