As the title says: When I take off from a dig and feather my clutch I can see the RPM's bounce, not erraticly but enough to see it on the tach and hear it in the car, about 2-300 rpm's. When I give it more gas it steadies out and maintains a steady RPM, It seems to be related to the position of the throttle as in the same effect in second and third if my foot is depressed the same amount on the gas pedal.
Details:
b16A2 converted to obd1
P28
GM 3 bar map
Hondata s100 w/boost opt.
t3/t4
high flow pump
Stock FPR
990 injectors

How do I remedy this. Its not the IACV, the car idles fine with my foot off the gas no idle hunting there.
Its not a vacuum leak, I searched and checked all connections and hoses, and I hit full boost @ 11psi with good throttle response.
My only thought is that I need to modify my FPR to allow more gas to return to the tank at low load? anybody else got anything on this, If Im wrong please speak on it and back your arguement with fact.
The car runs like a bat outta hell, no complaints just when trying to creap in traffic it lurches due to this problem, the problem is only there under slight load if im stopped its fine, some FI guru come to the rescue.

 

bump for an answer please.

 

"seems to be related to the position of the throttle as in the same effect in second and third if my foot is depressed the same amount on the gas pedal."

check your tps sensor

 

checkin helms as we speak

 

ok its not the TPS, what I have discovered is it only happens under vacuum, like 17 to 15 hg/in on the boost gauge.

 

I'm going to take a guess and say it's a tuning issue. I have some strange anomalies with my tune. The drivability varies, and it's really quite annoying.

 

yah maybe a tuning issue???

 

same **** with me i think its my timing, i tweaked the afr's under vacum and it seemed better but i still get what your describe just not as bad no more.

 

maybe try another map sensor.....but the tuning could the problem....