Loss of power on new rebuild
 

87 GXL...

I've been chasing down a problem with my rebuild for weeks now with no luck in solving it. The problem is with a gradual increase of throttle to about 3300 rpm's the engine loses power and sounds like it's sucking for air. The port actuators retract at 3300 but if I go any further on the throttle they disengage because of the rpm drop.

The same thing happens if I go to about 3/4 throttle all at once however the rpm's will only hit about 1500.

I've checked for vac leaks, re-timed it about 4 times, made a ECU checker.. all fine no codes, checked AFM (replaced but no difference), grounded the beast to the point where I'm afraid to drive in an electrical storm. Checked compression which is 95 on the front and 101 on the rear. This is a new rebuild with about 8 hours of run time. The car idles perfectly at 800 rpm's and has no problem with a gradual increase in the throttle until about 3300 rpm's

Now it seems I lose power just about the point where the TPS is fully extended. As a matter of fact the same symptom will occur if I'm at 3300 rpm's after a gradual increase in throttle and push the TPS back in by hand. I checked the TPS with my code checker and adjusted until only one light is lit. What should I be checking next???? Could this be a mixture problem (seems to run rich)? Possible fuel delivery problem? (I need to get a fuel pressure gauge to check that), TPS issue? I'm at a loss and so is my car :( When do the secondaries kick in? Could they be a problem? Any ideas are appreciated!!!