Idle problem -- IAC motor

I have a '99 XJ 4.0L. A week or so ago I couldn't get it to idle. I would start it, it would go to idle for a split second, and then die.

I was out in the middle on nowhere on vacation so I went ahead and just had it towed to somewhere that could fix it quickly. Turns out the IAC motor just needed to be cleaned out, and that got it started. The mechanic told me that they could replace the motor for a bit extra if needed, I figured that wasn't worth it if it just needed cleaning out.

Well, a week later here we are and it happened again. Again I wasn't anywhere near home and didn't have any tools, so I just went ahead and cleaned around it as best I could and low and behold eventually she cranked up and got me home. Now, should I go ahead and replace this, or would it be something else that keeps getting this thing clogged up?

Also I've heard of people having problems replacing IAC motors that weren't from Jeep, so I'm guessing I should spend the extra bucks to get it from jeep over a place like discount auto parts? And how hard is the thing to replace myself? It's only around $150 to just have it replaced by a mechanic, worth the 50 bucks or so I'd save to do it myself? IE how tough is it?

Thanks.

I have a '99 XJ 4.0L. A week or so ago I couldn't get it to idle. I would start it, it would go to idle for a split second, and then die.

I was out in the middle on nowhere on vacation so I went ahead and just had it towed to somewhere that could fix it quickly. Turns out the IAC motor just needed to be cleaned out, and that got it started. The mechanic told me that they could replace the motor for a bit extra if needed, I figured that wasn't worth it if it just needed cleaning out.

Well, a week later here we are and it happened again. Again I wasn't anywhere near home and didn't have any tools, so I just went ahead and cleaned around it as best I could and low and behold eventually she cranked up and got me home. Now, should I go ahead and replace this, or would it be something else that keeps getting this thing clogged up?

Also I've heard of people having problems replacing IAC motors that weren't from Jeep, so I'm guessing I should spend the extra bucks to get it from jeep over a place like discount auto parts? And how hard is the thing to replace myself? It's only around $150 to just have it replaced by a mechanic, worth the 50 bucks or so I'd save to do it myself? IE how tough is it?

Thanks.

It's held in place with two # 25 torx screws. kinda hard to get at. take your time and don't drop the screws. Magnetic screw driver or torx bit work fine. I've used a pipe stem cleaner to clean out the passageway for sensor. Dale jeepman600@sbcglobal :smokin: :grinno:

Him, I tried a #25 torx screwdriver and it didn't fit. Are you sure that's the right size? Buying the screwdrivers one at a time so I'd like to try and get it right as quickly as possible and save more $$ ;).

Him, I tried a #25 torx screwdriver and it didn't fit. Are you sure that's the right size? Buying the screwdrivers one at a time so I'd like to try and get it right as quickly as possible and save more $$ ;).
i was wrong the throttle position sensor is 25 if i'm right. can't remember right off hand if you go to auto store tell them what it's for they can try it there before you buy, if you ask. can't get used to metric. dale :smokin: :screwy:

You could just go to your local home improvement warehouse and buy a pack of 1/4" torx bits for 5 bucks. Most are magnetic and the 1/4 drivers are a dime a dozen. There's not a whole lot of other uses for torx screwdrivers of that size for anything else around the house or vehicles that I know of. ( Just how many turn signal bulbs burn out over a lifetime?)

Well cool, that wasn't too difficult. Only tricky part was getting to that screw in the bottom of it, my screwdriver was just a taaad too long and wouldn't fit in there so I had to improvise a little bit.

No jeep dealerships around here so I had to go with one from Advance Discount Auto Parts, hopefully these things hold up better than I've heard.

As for cleaning, where exactly should I be cleaning it out? I got some carbon breakdown stuff but not exactly sure where to put it. In the passageway between where the front of the IAC is and the Throttle Body (it gets really narrow inside and moves at a sharp right angle) or in the big huge air intake duct?

If it's the air intake duct, how the heck do I get that thing off? Unfortunately no other auto parts stores around, and the one I went to for the IAC motor was out of the Cherokee books. I can see that I need to pull back the clip and then pull the tab out from under it that locks it in place, but maybe I need to hit the gym or something because I put everything into it and couldn't get the clip pulled back far enough. Is there some kind of tool that's used for this?

Thanks in advance, I'm getting there.

Well cool, that wasn't too difficult. Only tricky part was getting to that screw in the bottom of it, my screwdriver was just a taaad too long and wouldn't fit in there so I had to improvise a little bit.

No jeep dealerships around here so I had to go with one from Advance Discount Auto Parts, hopefully these things hold up better than I've heard.

As for cleaning, where exactly should I be cleaning it out? I got some carbon breakdown stuff but not exactly sure where to put it. In the passageway between where the front of the IAC is and the Throttle Body (it gets really narrow inside and moves at a sharp right angle) or in the big huge air intake duct?

If it's the air intake duct, how the heck do I get that thing off? Unfortunately no other auto parts stores around, and the one I went to for the IAC motor was out of the Cherokee books. I can see that I need to pull back the clip and then pull the tab out from under it that locks it in place, but maybe I need to hit the gym or something because I put everything into it and couldn't get the clip pulled back far enough. Is there some kind of tool that's used for this?

Thanks in advance, I'm getting there.


If you use the red plastic straw that comes on the throttle body cleaner can. spray it into the slot using shot bursts, while holding the jeep on a high idle. DALE