I had to replace the battery. My reset didn't work 100%. It stalls a lot now. I want to change the IAC, but I don't know how. Please help. Thanks!

 

well, on the 4.6 L the IAC is on the driver's side, and it is silver, and a cylinder shape on the throttle body area. try cleaning the IAC before replacing it. the DPFE sensor manages the EGR valve, and can cause the truck to stall. what makes you think its the IAC? does the truck miss going done the highway, or does it stall at idle? it could be a vacumm hose, or the EGR system, it could also be the coil packs... really need more info... is the light on?

 

No lights, and it just stalls at idle (stopping or going around corners). It started right after installing the new battery. The "reset" procedure almost fixed it for a while, but my latest attempt tonight had no apparent affect. In fact, it seems worse. Maybe because I had to stop for gas 15 min into it. Anyway, I read in another thread that the computer would adapt to a dirty IAC, and the reset may or may not work until you clean or replace the IAC ("10-minutes tops"). Well, it sounded good but I couldn't locate it.

Should I try pulling the positive instead of the negative battery terminal loose? Just wondering.

The stalling could get someone killed. There should be a procedure that works every time. I get the feeling it's a hit or miss type exercise, and you have to drive just the right distance at the right speed, on the right road for it to work. I hope the battery never gets disconnected on my 4.6 Mustang.

120,000 problem free miles, and then this.............

I should've just sold it when the battery died.

 

You may have knocked a vacuum hose loose when replacing the battery. I am not sure about the 4.6 but they may have some vacuum lines running near where the battery is and they may be corroded and when you took the old battery out may have finished the damage to them.

It does not matter which cable you take off the battery. Any cable will take power away from the computer and that is what is needed to reset it. It is safest to always remove the negative battery cable rather then the positive. If you leave the negative cable on and remove the positive you can create sparks with the positive cable if it touches metal and possible short out the battery. Batteries also have some gases around them and sparks could possible make them explode and that’s why when removing cables you should always remove the negative cable first.

The problem you mention about stalling has nothing to do with resetting the computer. Yes it does take approx. 10 miles for the computer to recalibrate (learn) but the worst that happens during this time is the truck may not run great, like feel underpowered etc. It will not stall out and/or stumble.

I would recommend you check to insure you do not have any loose and/or damaged vacuum hoses. If you can not find any visual problems then I would take it in to someone for further assistance.

Another interesting note is batteries have a normal life of about 5 years…

 

The IAC is a cylinder about 2" in diameter that is attached to the intake manifold at or near the butterfly. Look aroung the intake manifold where your throttle cables attach to the throttle body and you will be sure to find it. It works by bypassing air around the throttle butterfly to adjust idle speed. The passages in the IAC are only a few millimeters and if they get too restricted the computer cannot open the IAC enough to get the air flow up. Hope this helps. I would really try agian to fiind and clean the IAC before I tried doing anything more drastic

 

Thanks guys

 

Hey, does it have some very small tubes or hoses going to it, and do I have to remove anything else to reach it?

How do you clean it?

 

It fixed itself. Is that a great truck or what? I went to get some carb cleaner to clean the IAC with, but I'll wait to see if it stays fixed first

 

Can you re-use the gasket?

 

yes, you can reuse the casket if it is not damaged. also, to locate the IAC on the 4.6L, you need to remove the large plastice cover with the 4.6L logo stamped on it. the black covers is over the top of the throttle body, and IAC valve. hope this helps...

 

That helps a lot. Thanks! The problem is intermittent again, so I'll clean it as soon as I can.

 

I have the same year and engine with 105k. Should the IAC be cleaned as part of my regular maintaince? As an original owner I know mine has never been touched.
Thanks

 

After resetting your computer, did you ever allow it to idle for about 10 minutes before driving it again for the first time to give the computer time to 'relearn' it's idle properties like the manual states? The problems you are describing sound like you just started it up and took off.

 

YES! My dealer has been cleaning me out every time I take it in!

 

If I am not mistaken, this is the IAC.



BTW: This is my engine, should that tube, at the bottom of the pic, go in all the way.Looks like it is a 1/2 inch out.