Idle air control on my F150

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4spdragtop

4spdragtop

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Ok, trying to diagnose some problems. Here is some info
2001 f150 4.6L 2wd auto
rpm's fluctuate intermittently and at any speed
truck will actually shut off..when this happens, I shift to neutral and try to start...all it does is turn over. If I pull over, shift to park, shut truck off and restart, it starts right up.
I checked pwr at IAC, Im getting approx 12v so I assume voltage is good.
I checked for resistance across 2 pins on IAC, I get approx 11..I assume good as they are within specs of serv manual.
I check for short to ground..1 probe from ohm meter on 1 terminal and the other probe on housing of IAC. Manual says at least 10k ohms of resistance, but I cant get a reading on ohm meter and my meter goes up to 200K(2million ohms) and as low as 200 ohms..I have tried all ohm settings with no reading. I believe it is out of limits and there is no short to ground..any suggestions/ideas?? I took it off and cleaned it out...I was expecting more carbon in there, but it wasnt really that bad...cleaned with carb/throttle body cleaner. New IAC is $120 and I just dont want to throw parts at it, as I am near broke LOL

Thanks
4spdragtop
 
I have never seen a Ford IAC litterly shut a vehicle off but I certianly haven't seen everything. When you cleaned it did you move the plunger back and forth to make sure it was free. I have had them hang up some times and cause our Fords to run like dog crap. I also always oil mine with a dab of cooking oil after I scraped all the carbon off, soaked it with carb cleaner in a spray can, double checked for more carbon, more carb cleaner for a final rinse then the oil and made sure they operated freely.
 
Same thing happened to my brothers F250.
IAC unit went.
Super eratic idling and dies for no apparent reason.
Also his would backfire through the intake and die, then not start.
Couple of min later it would fire right up.
 
The Borg Warner part number is Part # 31010 and sells retail for $47.99 locally.

ExpeditionV8 - 4.6L vin 6 281ci - MFI GAS SOHC 1998 - 2000

ExpeditionV8 - 4.6L vin W 281ci - MFI GAS SOHC 2001

F-150V8 - 4.6L vin W 281ci - MFI GAS SOHC 1997 - 1999

F-150 BaseV8 - 4.6L vin 6 281ci - MFI GAS SOHC 1997, 1998 and 2000

F-150 BaseV8 - 4.6L vin W 281ci - MFI GAS SOHC 1997 - 1999

F-250 BaseV8 - 4.6L vin 6 281ci - MFI GAS SOHC 1997 - 1998

F-250 BaseV8 - 4.6L vin W 281ci - MFI GAS SOHC 1997 - 1998
 
Rock Auto Prices.

STANDARD MOTOR PRODUCTS Part # AC214T T-Series $34.99

STANDARD MOTOR PRODUCTS Part # AC214 {Click Info Link for Alternate/OEM Part NumbersF65E9F715GA, F65Z9F715EA, F65Z9F715EB, F65Z9F715HA} $42.79

AIRTEX / WELLS Part # 4J1036 {Click Info Link for Alternate/OEM Part NumbersF65E9F715EA, F65Z9F715EA, F65Z9F715HA, F67E9F715BA, F67Z9F715BA, F67Z9F715BB, F75E9F715AA, TV229} F65E-9F715-EA $45.79

MOTORCRAFT Part # CX1874 {#F65E9F715HA, F65Z9F715HA, F6AZ9F715FA}
F65E-9F715-EA,GA $67.79
 
Check for a hole or leak in the formed PCV hose. It leaks right at the bottom of bend at the top of the Throttle Body but check entire hose.
Common problem
 
67DARTGTCONV said:
Check for a hole or leak in the formed PCV hose. It leaks right at the bottom of bend at the top of the Throttle Body but check entire hose.
Common problem
Click to expand...

You are calling it the wrong name. Fords don't have throttle bodies on these.
That would be a cheap fix if a hose is the problem.
 
4spdragtop said:
Thanks guys, pcv hose is the one that leads to the back of the throttle body??
Click to expand...
Follow it from the right valve cover and behind intake unplug it from the intake and you will see that the rubber elbow has either a hole in it or cracked.
I change them really regular here but usually will throw P0171 OR P0174 code(bank 1 and 2 lean codes) or both....Here they run about 32-42 dollars...Dealer only and will come with new pcv valve as well...
I start with the hose because I know it need to be changed....
If it is leaking the IAC valve will have a hard time keeping up...
Martin
 
4spdragtop said:
Thanks guys, pcv hose is the one that leads to the back of the throttle body??
Click to expand...

I just did a quick looksee at the f-150 forum and the two options that were listed was a dirty IAC or a vacuum leak. The vacuum leak seemed to be a common issue as Martin said.
 
Thanks guys will chk the pcv hose in the AM. I was at dad when I started this thread and on the way home it stalled again....not stumbling as much but still doing it. We cleaned the IAC, and the rubber cup seemed to move about 1/4" at most...stays where I move it to. Maybe the spring inside it is weak??
 
Oklacarcollecto said:
You are calling it the wrong name. Fords don't have throttle bodies on these.
That would be a cheap fix if a hose is the problem.
Click to expand...

Throttle Body is the correct name. I think you are thinking of the same name TBI's on older GM's with the injectors inside them??
I can't remember exactly where the PCV hose leads to on top even though I have done a few of these. Been a while.
 
Ok well I checked the pcv(stupid me shoulda known where it is) and its fine...looks like ford put it in 2007 as it had OC07 stamped on the side. The hose itself looks like a pita to change, but t has rubber foam heat shield around it and I checked the shield and not worn thru. So I am assuming good here. I read on the f150 forum that if I fire the truck up and unplug the IAC if the truck dies then the IAC is good. I did that and the truck died, so again I am assuming iac is good. Do you guys suggest to remove the throttle body and clean it out??

Thanks again!!
 
Is the CEL on? A vacuum leak will cause a code. Usually an IAC will not.
 
Where the Pcv Hose assembly normally break is behind the intake/throttle body,it is a rubber elbow and you can run your hand along the pcv hose and reach back there and feel that elbow it will be squishy and I bet it is sucked half closed and cracked....
Martin
Do you have any check engine codes?
 
For what it is worth. My wife has a 1995 Ford Bronco 5.0 and she was having issues with the idle fluctuating. We replaced the TPS and it made a big difference.
 
StrokerScamp said:
Is the CEL on? A vacuum leak will cause a code. Usually an IAC will not.
Click to expand...
Yes It would and generally A P0171 or P0174 ,Bank 1 and Bank 2 Lean codes.
I also do not like just throw parts on it...I do not mind replacing parts that are failing anyway...If it is not throwing the check engine light it is probably the IAC valve but that PCV hose does need to be changed !!!(especially if original)
Steve behind that foam pad is a hardline plastic and it will be good !!!
Only goes bad at the rubber elbows one at the PCV valve and one on the other end !!!
Martin
 
67DARTGTCONV said:
Throttle Body is the correct name. I think you are thinking of the same name TBI's on older GM's with the injectors inside them??
I can't remember exactly where the PCV hose leads to on top even though I have done a few of these. Been a while.
Click to expand...

In the salvage circuts on the Hollander Interchange System it is called the throttle valve or the throttle valve assembly but I couldn't think of the name yesterday :banghead::banghead:. O'Reilly Auto Parts and NAPA Auto Parts doesn't show it under either name. I guess it is like soda verses pop, depends on where you are as to what it is called.
 
TPS would likely set a code. Do you have a scan tool?
 
Oklacarcollecto said:
You are calling it the wrong name. Fords don't have throttle bodies on these.
That would be a cheap fix if a hose is the problem.
Click to expand...
they do have thorttle bodies they DON'T have TBI (throttle body injection)

aftermarket performance assemblies ARE called throttle bodies
 
Well I ordered up the Motorcraft part from Rock Auto, so wait for it to arrive, then install. Hope that solves it!!
 
Installed new IAC, now the truck runs worse. "service engine soon" light is on dash. Lots of vacuum when I unhook the pcv valve from the hose. So Im assuming no cracks/breaks in the hose. pcv valve isnt all clogged up, but spring feels kinda weak so Im going to replace it as well. Any other suggestions
 
4spdragtop said:
Installed new IAC, now the truck runs worse. "service engine soon" light is on dash. Lots of vacuum when I unhook the pcv valve from the hose. So Im assuming no cracks/breaks in the hose. pcv valve isnt all clogged up, but spring feels kinda weak so Im going to replace it as well. Any other suggestions
Click to expand...

Have it checked for codes.
 
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