High idle until stopped

A bad temp sensor would also throw him into open loop mode. I'm wondering if the OP can figure out or has access to a scanner which allows him the info to see open or closed loop.

 

I have an obd reader that does more like running diagnosis And smog sensor stuff
Lol wounder how your name did that

 

Hahaha yeah that's sort of weird

You know that OBD reader should work okay in diagnosing the problem. As long as you could see sensor information. If it is bad, it will stay at a consistently high resistance.

 

Im going to try. Need help. Some of it you do while driving. Ill post when i try in the next couple days. Thx

 

Ok heres the scoop. i plug that reader in and it came back with 4 codes. P0300 random misfire, P0102 P0103 masS or volume air flow circuit low & high. And P0125 insufficient coolant temp for closed loop fuel control.
these were called pending codes when I called the manufacturer of the computer they told me that I need to bring the truck in and have it fixed supposedly these people are ASE certified and pending codes mean that they are trouble codes broken but its not causing a malfunction in the engine. they told me that is why the check engine light has not come on. I don't know if these people are full of s*** but all the trouble codes and what seems to happen all makes sense.

 

Took the truck in today. Will post as to come.

 

They had more smoke. Nothing good to report. Codes still remain.

 

I had the same issue with my '03 Wrangler and solved it, since these engines use similar sensors and components to control idle here is my solution:
High Idle solved: I have been having a idle issue with my 4.0l, it would idle between 1300-2000 but usually would hover around 1500. I cleaned the IAC, throttle body and harness connections to the sensors ( MAP, TP, Air temp sensor). I hooked up my ODB and I could see that the TP was sending the correct signal. Then I checked all the vacuum hoses using the carb cleaner method (with the engine running, spray it on all the vacuum hoses and see if the engine rpm change). I still had the issue, after pricing the sensors I decided to just start replacing them since they didn't cost that much, I also opted for Mopar since the chinese ones were getting mixed reviews. I got the IAC for about $50 but nothing changed after I installed it, next was the MAP($65) and that fixed the issue. I also learned a MAF sensor has the air temp sensor built in while a MAP sensor uses an external air temp sensor. The air temp sensor would have been my next item to buy. The only thing I would have done different is to have bought the MAP first, it is usually this guy that fails

 

If you want my advice I wouldn't had brought it in. I would had also cleared all codes. Take it for a spin, let the light come back on and when it does, THEN you will have the code which is the trigger for all the others. Guaranteed either your MAF is bad, or your coolant sensor is or both, and those are in turn triggering the misfire.

 

So, where is there a sensor that knows when the wheels are turning and when they stop, and reduces idle then?

 

You would be referring to the ABS sensors. They have NEVER had any influence on idle ability on vehicles though. What makes you think that they do?

 

What he said. My 2000 has this same issue with the idle and I have no abs on my truck.

 

Pending codes mean these items have failed but have not failed often enough to trip a light. You have a bad MAF sensor and Temp sensor. That will fix your issues. The computer is not registering you are hot enough for Closed loop mode, therefore you are running in Open Loop mode(extremely rich fuel to air ratio), and it's also making it idle high. Bad MAF sensor won't let the computer know how much air is coming in, and also the temp of the air. That is going to make it run extremely rich as well. Your misfire could be due to it running very rich.

 

What about the coolant sensor open loop? Should i start they're instead?

 

^^ ?

 

Mine finally threw a p0120 code... throttle position. Not sure if just need to clean throttle body and everything really good again or its the actual tps that is bad.

 

Not saying this is not your issue but I replaced mine with a brand new one due to the weird idle sometimes and it didn't help that. However I did not have a check engine light for that.

 

You need to delete the codes (after you've written them down) test drive briefly and then recheck for codes. The first code that comes on is your problem which is triggering the others to throw their codes. Like a domino effect. You start at the source and work your way out after that. It being a newer truck I cannot see it being a bad wiring issue, though things happen as these are after all assembled by man, and if they are by machine, they are still calibrated and controlled by man.

You know what you need to do now. I don't know why there is still questions about this. What's the confusion bud?

 

Thank you