pontiacformlt1

The car is having a starting and idling problem.

When you start it it will bog to ~200 rpms and almost stall and then a second later it smooths out. When it warms up it starts jumping up and down in idle between 1k and 1800 rpms.

I pulled the TB off and removed the FITV and cleaned and tightened it. Also cleaned out the IACV and put it back on. No change.

I decided I would go ahead and try the TB hole plug test (pluging the holes in the bore of the TB) and the top one (these are on the rear of the bore closer to the firewall) sucks my finger into it and the idle levels out as the bottom one (fitv passage) barely does and changes nothing.

My diagnosis is the IACV is sticking open and when I hold my finger over it the plunger closes.

Can anyone confirm if I am correct here?

GhostAccord

Yes the top port is the IACV port. So your deduction would be correct that it is stuck wide open.

Make model year of Accord & year and model of the H22 would be beneficial. Also what ECU you are using and how you have the IACV wired?

pontiacformlt1

Its in a 92 accord sedan with a P13 ecu and wiring i am unsure of since it is not my car. The guy bought it swapped and it had no problems up until about a month ago when the symptom I am chasing started.

Is there a way to test to see if it is infact the IACV is bad or if its wiring keeping an open circuit?

nus_dogg

I'm not sure if there's any way to test the IACV. If the car is fully warmed to normal temp, and all of the sudden the car started the problem you've mentioned, I would say its the IACV. Because after the car is warmed up, the IACV comes into play and takes over the idle.

FITV is what controls the idle when engine is cold, so if FITV is bad and engine is started up cold, then it'll cause the engine to idle surge from what I understand. Hope this helps a little.

GhostAccord

Take the IACV and attach a ground wire to the IACV (-) pin (BLK/BLU wire). take a piece of wire and attache it to the (+) terminal on your battery. Momentarily tap the 12v wire from the battery to the (+) pin on the IACV (BLK/YEL wire) If the IACV clicks then it is working and you should test the wiring between the IACV and the ECU/Ground. Worst case scenario, try another P13 ECU and see if it is a defective ECU.

pontiacformlt1

I tested it on a battery and it clicked fine when I did.

GhostAccord

When the engine is up to temp and you unplug the IACV do the RPMs drop or change at all?

pontiacformlt1

ok so i went out this morning and let it warm up. I pulled the plug off it and it dropped to ~800 rpms. i covered the port again and it wanted to stall out but there was still quite a bit of suction.

I turned the car off, reset everything by pulling the 7.5 amp backup fuse for 60 secs. and then restarted the car. while it was running i sprayed some carb cleaner around to see if there was a vacuum leak and no leaks were detected.