Idle Issue

[Xfinalresort]

Well im fairly new to this forum thing, but here it goes. I have a 1999 civic si with a B18b1 lsvtec with a idling issue It will go up and down constantly between 1k and 1.5k Rpm's and again at 500 to 1k Rpm's with my chipped p28 but when i put in the P2tT ecu it runs fine and idles fine. it has a 2 wire IACT conector and i checked the wiring and it comes out fine. I had also cleaned the IACT on top of the intake manifold with running hot water. Didn't help one bit...

I ran out of ideas, and decided to turn to this forum once again. You guys are great!

[Inline4]

bump prob the p28

[Xfinalresort]

Bump thanks but im thinking it might be the Jumper harness about to check the wiring on that in a few hours.

[Sly]

GL

[Can~i~bus]

Calibrate the tps

[Xfinalresort]

I put a multimeter to the middle wire on the TPS and it reads .46@ idle and 1.57 at WOT. One again I have no clue what's going on.

[Xfinalresort]

bump

[Xfinalresort]

Bump before work...

[ls94civic]

Sounds stupid but...... Have you checked your coolant level?

[Xfinalresort]

Yeah it's fine. I ran a search on it and that was one of the first things I did. Had a little change on the idle.

[Xfinalresort]

midnight bump.

[kbrown!]

Disable the iac and see if that fixes your issue.also does it do it all the time or only when it cold?

[Xfinalresort]

It will do it all the time. But ill give that a shot tomorrow after work, then ill report back here on my findings.

[Xfinalresort]

Morning status update: well I did the above and it idles fine. I unplugged the IAC and it runs like a clock. No surge and stall but I did pop a CEL. Does this mean I need a new IAC valve?

[94EJ1OwnS]

Most likely itd the chip p28 , if your stock b16 ecu runs fine then either that chipp p28 isnt right for your car but try another p28 maybe a stock one & still see if itd idles juss like the chipp one