When I did my tune-up recently, which was a piece of cake thanks to the Jeep being self-adjusting with the timing, the only thing that wasn't great is the current idle speed, which hovers around 250-300rpm, often feeling like it's studdering and wanting to die, even though it never has.

I was told when I asked that I needed to clean or adjust the TPS. I have zero idea how to do this...

Where do I find out about adjusting it? Any tips? Is it easier, since I have 230k on the engine, to simply buy a new one and install it?

Any help is greatly appreciated, thanks so much

KK

 

It tells how to adjust the TPS, and other things, in here. Jeep Cherokee Engines - RENIX (non-HO) Engine Sensor Diagnostics

 

Did you clean your throttle body inside?

 

ugh, I lost this post and forgot to reply...

First off... thank you Blue. I'm clicking on that link as I type

And um, regarding the TB... no, didn't clean it. Have no idea how to, actually... is that something I need to do?

 

If your TB has grime around the throttle, it will idle roughly and low, due to air flow reduction.
Check your vacuum supply to the map sensor too.

 

ok, thank you, I'll go do some research about how to do all that.

Appreciate the help

 

I had similar issue. I replaced both o2 sensors, still rough. Replaced TPS, still rough. Removed and cleaned throttle body, IAC sensor and valve, works so far.

Its not too hard, just time consuming. Get some throttle body cleaner from the parts store. Disconnect your battery, unplug all of your sensors to the TB, remove your air tube, then remove the 4 bolts holding the TB. They are 10mm. Remove the IAC sensor and valve. Spray the cleaner on said parts, wipe and clean thoroughly with cloth and Qtips. Reattach everything you took apart and you're good.

If you search on jeepforum.com, there are a couple write ups if you like pictures. Hope it helps.

 

That was awesome, thanks so much!

 

I thought so goo but didn't work for me. It was good at first, but I may need replace my IAC with a new one. This is so frustrating

 

Is replacing them the simplest way? They're just wires with harnesses on them, yes? well, not the TB, but the TPS and IAC sensors? Ugh, this is a realm I know very little about... forgive me if I asked the question wrong or made incorrect assumptions

 

it is simple,just unplug and remove them from the throttle body and replace with correct ones. Be careful to get tps back where it was,make sure to reinstall o-ring on iac and that old one is out,and do not overtighten,the throttle body screws strip very easy.

 

So I did this yesterday... at least, I tried to.

Maybe y'all can help?

I removed the IAC, cleaned it with TB cleaner, no problem. Can't get my air tube off of the throttle body though... someone before me stripped the screws, nothing catches so I can't unscrew it to get to the throttle body!

What do I do? I don't want to drill it out (dont' know how to, really) and I really need to fix this idle problem... do y'all have any suggestions for getting that dumb air tube off of the TB so I can pull it and clean it? =\

Cleaning the IAC didn't help my idle at all, either =(

 

Try gripping the heads of the srews that hold the air tube with vise-grips,or there are srew removers.just cleaning th tb bumpt my idle from 650 to about 2200

 

Kodiak, do you still have the low idle problem? I finally fixed mine. This is what happened...I stripped the o2 sensor wires with my driveshaft while wheelin. Driving through mud and water shorted a fuse under the hood. This caused the o2 sensor to send a high voltage code.
My fix was simply replacing the 20 amp fuse under the hood. Since I did that, no problems. Not sure if its the same thing you're dealing with, but I ended up changing both o2 sensors, IAC, MAP and TPS. If I just checked the fuse first, I could've saved a lot of cash!

 

I haven't been back to this thread until now... oh man, that sucks, but it's good advice. I'll check my fuses before I start spending money! Thanks again