Will a dirty IAC cause the following problems?
1) Heater will not blow threw floor or panel
2) cause the front tires not to engage when the 4 wheel drive is engaged
3) make the engine hunt I.E. when I crank it up the rpm's shoot from 450 to 2000 three or four times...

Thanks for the help
Jay

 

Hey-

1) No it will not cause your HVAC problems. This could be a blend door... not sure
2) No IAC does not control your 4wd....
3) This is more in line... maybe..

What the sr. guys are going to ask you is :

What year?
What Model?
What Engine?
How many miles?

Also the IAC is the Idle Air Controller. Which would have NOTHING to do with your first two problems

 

What kind of truck

Fill your info in - top right corner.

 

2003 Ford F150 FX4 Lariat extend cab sportside 5.4 litter 70,000 miles

 

Fixed.

 

So I crawled under the truck last night. I found the Actuator on the front axle. With the truck off I moved the plunger in and out several times. I then had my wife get int the truck crank it up while I was under neath it and engage and disengage the 4 wheel drive. I watched the plunger move in and out on it's own. So I then decided to take the truck into the field to see if the front tires where pulling. They weren't at first, It took them about 5 mins or so of driving around for them to engage. After that I locked it into 4 wheel Low and it went in fine and tires pulled really well. So then I took it all the way out of 4 wheel and drove the truck a down the road a few miles in 2wd. I then went back to the field and put it back into 4wd and all worked find right off the bat. Does any body have any idea what is going on with the 4 wd. Was the motor just stuck or something..

thanks for your time
Jay

 

Could be, especially if you recently acquired the truck. Some people buy 4x4 and never use it. I try to get off onto some gravel or grass at least once a month and cycle through 4hi and 4lo just to make sure things don't get gummed up. I would cycle through it a few times.. drive around in 2 for a week and try again. See if that fixed your problem.

 

I had a 4x4 issue at the beginning of winter. Use the search function
(above-3rd from the right).
Type in 4x4 problems or something along those lines and you will pull up a bunch of threads about that issue. In my thread, anything that can be checked and/or repaired is in my thread.
Jbrew went through and maitenanced his system not long after I found my problem. JMC has some good info on this subject as well. He helped me with the service and mait. on mine and Jbrew followed the same advice.
As usual, Jbrew wasn't having a problem, he serviced his to prevent any problems. Jbrew is the preventitive maitenance king. I thought I did alot of prevent, Jbrew goes alot further with his.
If you don't have any success with the search, let us know, we can point you in the right direction. There is a few Ford Techs on here who can definately help you out.
Good luck with it, keep us informed.
TJK

 

As tired as I am, I found my threads.....
Read through them, they got excellent pic's as well.

https://www.f150online.com/forums/ot...issue-now.html

https://www.f150online.com/forums/v8...nt-engage.html

Good luck with the fix.

I have some more info in my head about this problem if you cant get it fixed. I'm way to tired to go through that right now.

 

It is kinduh late for you. I can here the wife yelling at yuh in the back ground. - You better get to bed man.

 

The wife was passed out when I got home at midnight.
Long story short version. My niece is expecting the baby due any day now.
Got a ALOT left to do to complete the baby's room. What do we do, Call Uncle T.
I am still shocked, the entire room is done, I finished cutting the carpet in at 10:30 last night. I did have my sister call in one reinforcment for an extra set of "hands". Trashed my back again in the process.
No, I never learn, that is why we have Back Cracker's and liquid Advil.

Oh ye, back to Ford stuff. My 4x4 didn't have a problem all winter, thanks in part to JMC's info and tech. pictures.

 

Thanks for the help gents.. I just started looking at some of the stuff yall posted.. Well the other day I wrote an update and thought I fixed it.. Well I didn't over the weekend I tried to engage it again and the front wheels still wouldn't pull.. Until i stuck in Neutral and reved the engine up.. I then out it into drive and low and behold the front tires strated grabbing. So I am going to go threw yalls threads and see what I can see. As for the IAC and the heater/AC haven't even started on it yet.

 

GIjay,

If you really want to know what your IAC (idle air control valve) does, open the Google link below. I can sit here and type out what the function of your IAC is and if your having a problem with it, I can write up a cleaning proceedure to help the performance of the valve.
I find it much easier to read on my own from a web search, in this case, Google.

http://www.google.com/search?sourcei...rol+valve+ford

There are alot of "hits" for you to open and educate yourself.

By the way, from reading your 1st post, if you are having a problem with your heating system and 4x4, there is a good chance that you may have a vacuum leak somewhere. Your heating shutter doors (under the dash) and your 4x4 actuator are vacuum operated.

 

I would agree with you about the Vacuum leak.. My dad works for ford and Powerstroke. He put me in touch with one of his dealers and they said the same thing. But when I take off the vacuum lines there seems to be good vacuum...

 

I don't know where you are testing for vaccum or if you used a vacuum tester. If you pulled any vacuum hose and put your thumb over it and said,
"ye, that has good vacuum" not a good way to test it. You need to pull the vacuum lines from the source problem areas and see what your vacuum is reading. There are a few people on this site who found that they had damaged vac lines going to the 4x4 actuator.