i got a 98 GS-R with a b18c1 in it....having a issue when it comes to fuel trim and i know its gunna throw a lean code once i start driving it....

i recently rebuilt the engine myself (very experienced when it comes to b series engines) but this problem was there before i took it apart

PROBLEM: when i first start the car cold it starts rite up and idles at about 1500 RPMS (normal) after a minuet or two the rpms drop all the way down to like 200 RMPS for like 10 seconds then revs itself back up and idles fine at about 1200...

When the car hits closed loop it idles at about 800 RPMS....i got a hand held scanner and i monitor the short term fuel trim and i notice it goes all the way up to 46.9% sits there for a second then resets itself at 0 and starts to rise again by about 2% a second all the way up to 46.9% and does it over and over again...

i was told before i took the engine apart that this could come from a vaccum leak so i replaced the intake with a victor X intake figuring that was the problem

Things i replaced: IAC, IAT, The ECU itself!, o2 sensors are new.

so my next step is to run a vaccum test on it hopefully thatll turn up fine but ill keep u posted on the resutls.

please only reply to this with serious answers i dont wanna fill this post with bs im rlly in need of help

THANKS!

 

Sunday bump

 

tuesday bump...

updates...tested ELD (electronic load detector) and everything was in line

also tested map sensor and that checked out fine too.

HELP!