99 QX4 IACV question

[BravoQX4]

Newbie here, I have a 99 QX4 and pulled up a P0300 code with a pending P0505 IACV I plan on replacing this soon as it now stalls sometimes at idle. Question is, is the plenum removal necessary to remove and install this since it is located on the upper air intake plenum and has anyone done this that could give advice?
Thanks in advance.

[Leo1998]

yes the plenum removal is necessary because its bolted underneath it. There's a hose that leads to it that people have sprayed Throttle body/Carb cleaner down to clean the valve without removing the plenum, I tried it but later discovered it was my MAF sensor. I didn't have any codes to tell me it was the IAVC. But when i did remove the intake for something else i removed the IACV to check it out and it was pretty clean! so it's a cheap try at the most.

[BravoQX4]

Thanks Leo1998 I'll give it a try.

[Leo1998]

There's 2 tubes coming off the air cleaner ducting in the front, one goes left i believe and the other if you follow it goes under the intake, that's the one to spray cleaner down. I sprayed enough to come back out the tube, hooked it back up, cleared code, start up and see if code comes back. I didn't have a code when i did it, i did it because it was idling bad and ended up being the maf. You will see some tailpipe smoke from the cleaner being burned up. and maybe a hard start too. Might have to try more than once. In the end if you take off the plenum get a PCV valve too because it's under there also.

[Leo1998]

also if you take off the IACV you can put power to it and watch to see if the plunger cycles or not.

[jallider]

I would take it off and give it a good cleaning. They very rarely go bad. Just carbon build up. Also, clean your throttle body while your at it.