Now, a problem arises.. performance hasn't seemed to change. Still lags after driving for a while.. but now, it will NOT idle below 1100RPM.. cold idle is about 2200 rpm <img src="/forums/images/graemlins/confused.gif" alt="" />

Latley, it has been acting like the fuel pump is being shut-off entierly, then turned back on, and it will do it at random.. I cannot replicate the problem.. completly random <img src="/forums/images/graemlins/frown.gif" alt="" />

Under what conditions does this happen? ie is it under slight throttle, very light pulling or, is it under more heavy throttle conditions?

TPS problems could cause both of these.. The TPS switch "home" or throttle at idle position, is what tells the ECU to begin adjusting the servo operated idle air valve to regulate the engine idle speed. If the TPS "home" switch is not closing, idle speed will be fast and unregulated by the ECU.

The TPS also signals the ECU when to do the "fuel cut" or shut off the fuel injection system when coasting and your foot is off the throttle.. Incorrect settings here cause bucking as you go from no throttle to light throttle and vice versa.

I'd recommend a very through cleaning of the throttle body including the idle air control air path in the throttle body. Same question as in the thread below.. How you "tweaked" what looks to be the idle adjustment screw on the throttle body?

Read this thread for similar problems..

The no power when giving heavy throttle sounds like a MAF problem.. Is it any better after cleaning with the proper cleaning agent as mentioned in the MAF cleaning article?.. I don't know if brake fluid cleaner will permanently trash it or not.