I just attempted doing mine today, but found out that NAPA got me th wrong one, looks like the same thing only, the one they got me has one of the holes blocked off and a fitting on the backside of it for the idle air, must be for a 4.6 or another year i'm guessing. Easy job, even easier with a bodylift!

 

hi,would a bad iac throw codes,po171-po174.thanks

 

Nope

 

This article is still helping folks! My '03 KR was stalling on attempts to start with a warm engine, compressor was cycling continuously @ "idle" and throttle response was sluggish. I had cleaned the ole K&N, new fuel filter, plugs, etc. After 119,878 miles it looks like it was time to replace the IAC and now all is running great. Thanks for the posts, pics and guidance!

 

I noticed in your picture of the old and new IAC , THE OLD ONE shows a spring inside and the new not? why is that, great instructions, I cleaned mine today as I was doing throttle body anyway, thanks

 

Call it evolution...or a knockoff; -whichever the case may be.

 

I have an 02 supercrew with 5.6L engine. In May, it was idling rough and stalling. I changed the air and gas filters to no avail. Trustworthy mechanic changed the Idle control motor and it ran fine, but it idled high (almost 1.5K rpm) for the first mile or so, whether the engine was warm or cold, then it would be fine. Mechanic said that was normal (although the truck never did it before in the 10+ years that i have owned it). Recently it has developed this annoying hum, but only between 800-1.2k rpm. Both this mechanic, sorry technician, and one from a different garage have said it is a "resonance in the air supply". There are no engine codes, not does it seem to affect performance. Both say just accept it. Although my trustworthy mechanic- and i do trust him not to screw me- says he could search further for the problem if I really want to invest in it. Reading these posts could it be a faulty IAC? or is there somewhere else in the engine i could search for an answer? The humming really is annoying.

 

Probably an off-brand IAC valve that's a bit incompatible with the 5.4.

 

first of all I misspoke- the engine is a 4.6. After perusing all these thread on an IAC mooseing I opened up the hood and looked. yes the muffler was there and all connections seemed tight. I went to the parts store and bought a 12" piece of 3/4" heater hose and a nipple- cut it to 9" and 3" and inserted them in the run between the IAC and the air supply with the muffler still in-line replacing the little elbow hose that was there. The hum is gone! (a poster somewhere on this forum said that changing the length/direction of the air flow would get rid of the hum) The plastic cover over that part of the engine doesn't fit correctly anymore due to the extra hose but it does not seem to be a problem. Just waiting now to see if it affects my gas mileage- it was between 14-16 mph