Rough idle at dead stop only and P0135 and P0155 codes

Update: I am sitting in my running TJ at an average of 650RPMs whereas before, during the issue, I would average about 400RPM. Disconnecting the battery and reconnecting it *seems* to have solved the issue.

Upon startup this morning the MIL was illuminated and I had a solid P0155 error. I backed out of the garage, shut the sputtering engine down, and popped the battery cables. I did check to see if either cable was remotely loose and they were not. There was no corrosion on the posts nor the connectors. I reconnected and fired the engine up and initial idle was at ~1000RPMs, which for me is normal. I let it idle for about 5 minutes and the RPMs gradually dropped to ~650, which is normal. I then drove it for about 2 miles being sure to coast at idle as well as stop and idle. Everything was normal. When I got back I let it idle with no issue.

I’m going to drive it a bit today to see if the issue returns. First I am going to let the engine cool to ambient temp. I will update again as threads like these can be invaluable to other members and not having a follow up wouldn’t be cool.

Fingers crossed that this is all it is. I am hoping it is not a computer (ECM?) issue.
 
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Update: Cold start 100% normal. Let idle until completely warmed up with no issue. Made a round trip of 12 miles to gas her up for a total trip time of 21 minutes with the route including several stops, hills, and turns both right and left. No issues. Dead stop idle RPMs held at ~650 at the gas station and upon return. No pending codes.

So far I’m feeling good that this is resolved.
 
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Update: Fixed? Not really.

Yesterday I ran the Jeep for work. Upon starting the engine I got the dreaded low RPM issue. That continued with the same issue I was experiencing - RPM drop at dead stop idle. My trip to work is 25 miles, about 1/3 of the way the issue stopped. A little over 8 hours later I made the return trip and had no issues whatsoever.

This morning I decided to take the Jeep to work again. Everything was 100% normal except for to dead stops where the RPMs dropped. They were several miles apart in occurance.

At this point I know there is a problem. I don't know what the cause is. I may just order a new IAC since it is simple to swap out and relatively low-cost. The O2 sensors are on the not-too-far-out replacement list already so I'll keep that schedule and not expedite.

FWIW, I will keep updating as things happen.
 
Update: I do not have the issue resolved as of yet. The issue persists but is very intermittent - I will have runs that have rough idle frequently and others that have no issue. Usually I now only have one or two instances of rough idle during a trip. Regardless, it needs to be fixed.

I have just ordered a Mopar replacement IAC and will install that, expect an update next week.

EDIT TO ADD: The engine is still running better at idle after cleaning the IAC than it was when the issue started.
 
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Update: IAC replaced with Mopar part. The pic shows some “slight” variation. Note that in the pic the o-ring is missing from the new IAC, I did install it!

I’m sitting in my idling TJ. Initially all seems well. I’ll give it a few days since the issue has been intermittent and I previously thought cleaning the IAC fixed it.

I must say that the last three time out prior to this the issue did not present itself.

C9F4D7A7-0D2B-48CE-92B5-D174F3BE969C.jpeg
 
Issue remains resolved - zero idle issues and I’ve driven the crap out of it yesterday and today.
 
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