It has a 99+ intake on it that didn't look like it had any cracks when I pulled it, cleaned it and installed it. It has a HO TB on it so I had to keep my renix tps and adapted when I swapped a different one on. The IAC has been swapped with 4-5 different ones with no noticeable change. The new TB I put on did have an IAC in it when I swapped it. I have replaced the TB gasket a few times and a new one was used when this TB was put on.

 

The injector o rings have been replaced
The throttle body has been swapped a couple of times
The current IAC seems to be the best as far as idle, but it may just be the lack of air getting by in the TB it was put on with
The o2 sensor is working properly
No values read off of the REM seem out of place, so again I am stuck.
It idles around 1000-1250 rpm depending on the AC being on or off.
when first starting the jeep it seems to idle around 750 rpms with a little bit of bouncing, then when it goes into closed loop it revs up to 1000-1250 and seems to idle smooth, but high.

 

The o2 sensor stopped flipping rich to lean again, and I've noticed with the ac on it charges a lot lower than with it off. The electrical stuff on this truck is going to be the end of me.

 

Voltmeter reading low with aC on is normal.

Got power from the O2 sensor relay to the sensor?

 

Sorry this got buried in my subscribed threads. Last I checked it did have voltage. My boss rode with me the other day to lunch and noticed the high idle and o2 sensor issues and now he's determined to help me figure it out. We hooked the smoke machine up and I couldn't find any vacuum leaks. I'm not really sure what exactly to try at this point

 

The hold down for the distributor had been modified by the previous owner at some point and time so it didn't really hold the distributor as well as it should. If you bumped it hard you could get it to rotate. We put a new hold down on it and got it perfectly back to the right spot as per the window cutting TSB. We double checked the grounds to the sensors and they were all good. Under 1 ohm and when massaging the harness there was no change in the reading. The input of the tps was 4.90 and it was at .85 closed so we adjusted that down to .83. After that the idle was still high, but when it was set at .83 and we turned the tps up while it was running and then back down it would idle correctly until there was more throttle input by the pedal, but if we did the same thing with the tps again it would idle correctly again till there was more throttle input. Unfortunately the parts store near me didn't have one in stock so I didn't get to try a new one, but I can get one ordered at work tomorrow and maybe that will fix it? That's kinda where I'm thinking for the idle right now.

 

Well my ocd was bothering me that I had a computer out of an automatic Cherokee in my Comanche so I got a computer that is for a manual and the truck still idles high. Didn't really expect it to change with the computer, but thought I might as well give it a go.

 

1987 4.0 Can't find the part number for the CTS (on block just above oil pan) that has a connector similar to an injector.

Thank you for the help.

 

Probably one of those will work. Should really make your own thread for the most view/help. Not add into a thread about the issues of a specific Jeep. Rock auto has all the parts your car will ever need.

 

None of those are a CTS as installed on my Jeep - unless the connector is obsolete and needs to be changed. Given my Jeep is a Renix it seems to fit the thread "Renix era issues"

 

That's the knock sensor......

 

I guess I should've labeled it as my renix era issues then

 

So this Picture is wrong
Deep sigh - what a pain

 

I just looked up knock sensor at ROCK AUTO




Looks nothing like this

 

That is the knock sensor. They no longer make that exact knock sensor so it is replaced with the ring and bolt style one or you can get one at a junkyard.