My 2001 with 38K miles is starting to show what I think is an IAC problem. The truck occasionally wants to idle down to 300 or so RPM and wanna die at a stop. So I throw in the clutch and hit the gas. I'm hoping it'll hang in there till it warms up so I can pull the TB and clean or replace the IAC. It's freezin *** cold here and nowhere to work on the truck. My question is since a TB passes only air not air n gas how does it get all carboned up?

 

DIRT + OIL = GRIME---sucked in past the filter including a little oily mess that all vehicles have, IAC is like a plunger that opens and closes, gets dirty just like anything else.

 

Sounds like the problem. I have 110k on mine and I just cleaned it, was dirty as hell

 

Gentlemen: Thanks for replies. It's interesting how things have changed. In '64 I owned a '62 Corvette that had mechanical (not computer controlled) fuel injection. You had to adjust it for humidity changes. I hate this new ****, but I'm trying to keep up.

 

yea... get the tb off of there and clean the living sh*t outa it... ive made it a practice with every oil change now... along with a bottle of injector-b-clean scrub scrub scrub..clean the connectors for the 3 sensors too... and make sure you use some di-electric grease on them...makes it easier for a good connection especially in your climate and keeps them from ceasing .. like spark plugs do on the boots if they havnt been changed in a while or not prepped good with electrical grease.

 

oh!!!!!!!!!!! make sure your air box is seated correctly on top the tb... this happend to me to thought alot of problems...just dumbass me didnt mate the airbox to the tb good and had like a 1/4 gap on the one side.... i was half drunk and it was dark ... and the dog was barking....and windy... just a crappy day... anyway... having a gap like that for outside air to get in would cuase them symptoms too... goodluck..

 

Speaking of cleaning the TB. Yesterday I took off the plastic thing on top of the TB that has the air filter, because I was doing a tune-up and it was on the way when I was trying to get to the cap and rotor. Well the paper gasket broke and the part store said they didn't have it that it was dealer item. Now the plastic air filter thing seems to be a little loose without that gasket. I didn't wanna go get the gasket because I planing on buying a CAI in about two weeks. Will it hold that long? and I'm just assuming the CAI comes with a gasket, I could be wrong. Oh yeah and I cleaned the TB with some carburator cleaner, it's nice and clean now!

 

you could probably get away with poping the air hat off and shooting some TB cleaner on the IAC valve w/o taking the TB off. your best bet however is to remove the tb, the IAC valve and clean the seating area and plunger. you might also want to squirt a bit of lube on the shaft so that it slides easily.

you need to remember though that the intake is hooked up to the pvc valve that is there to help vent the motor so pressure does not build up inside the block. that vapor gets sucked into the intake and contains oil which will get on just about everything in there. it is normal and periodic maintanance is required on the TB to keep it working properly.

 

Thanks for all replies. It's supposed to get in the 30's over the w.e.. Maybe I'll grt off my *** and look.

 

... yea take off the tb..takes the most of 10 mins to take it off the motor... trying to shoot it with cleaner prolly help you out untill your fipk comes in... and that thing is apain to get toghet..directiosn suck... come here of you got any questions... that gasket does prevent air leaks between the airbox and the tb ( the plastic thing that has the fliter in it..thats the airbox ) you notice that gooffy lookin "hose clamp" that holds the airbox on tight to the tb... that is a pain to alighn correctly and will still tighten down without it being on there correctly... take your time and make sure its alighned and on properly....get your hands on a chiltons or haynes and itll help out alot!!!!! both manuals can be gotten at autozone or advanced... and the fipk does come with a new gasket and its alot thicker then the stock one... goodlcuk