2005 Idle Issue No Codes

[757speedaltcap]

Hello!

I recently purchased a 2005 Jeep Wrangler X with the inline 4.0 and manual transmission, 66k miles.

However, during idle I attached a video of what occurs.

How it happens most and how to get it to replicate:
1. Get to operating temp (around 210)
2. Drive to full speed of 50-60 mph
3. Wait to idle in neutral with AC off (not sure if AC on or off affects it)

During initial start up of cold engine it does not occur.

Recently mechanic cleaned throttle body and then subsequently changed the idle air control motor. Both of these have had no affect and it still occurs numerous times during a 20 minute drive.

Any suggestions would be great.

Again, no codes from the mechanics or from conducting the Jeep method of using the key 3 times.

Thank you!

 

[757speedaltcap]

Anyone have any ideas?

Thank you

 

[tr21triton]

did you clean your IAC with the engine running ?
https://wranglertjforum.com/threads/how-to-clean-your-iac-idle-air-controller-valve.662/

 

[Link]

I've tried to watch your video but can't get it to play for some reason. Describe what it's doing.

 

[swtrailboss]

Had this issue with my 2003 4.0 and cleaned the IAC and I replaced the IAC valve with no luck the issue was still there. After further searches on this forum an individual commented about replacement of the TP(throttle position) sensor correcting this issue. I did that and problem was corrected. Only when engine was warmed up would this issue be present.

 

[757speedaltcap]

Hey everyone, thank you for the replies! I will attempt to upload the video again. It worked the first day but even I can’t get it to load now.

What occurs:

During idle (after engine warm), it will idle normally for a few minutes, then drop suddenly and almost stall (it has not stalled completely yet) and simultaneously flash (very briefly) a check engine light while the RPM drops. Then the engine revs itself back up over 1300 ish and settles back at a normal idle around 700 until it repeats a few minutes later. The check engine light never stays illuminated and only flashes for a split second when the engine almost stalls. No codes have ever been picked up or are currently present.

 

[757speedaltcap]

Here’s an attempt at the video post again.

https://share.icloud.com/photos/045rdumTjk45xDw_xJcU-QwBg


Short iCloud link that may work?

 

[757speedaltcap]

Had this issue with my 2003 4.0 and cleaned the IAC and I replaced the IAC valve with no luck the issue was still there. After further searches on this forum an individual commented about replacement of the TP(throttle position) sensor correcting this issue. I did that and problem was corrected. Only when engine was warmed up would this issue be present.

Thank you!! I will research this more tomorrow. Can you view the video and does it match what happened to you?

John

 

[swtrailboss]

Thank you!! I will research this more tomorrow. Can you view the video and does it match what happened to you?

John

the engine idle would not drop that low but would rev upward to 1200-1300 rpm and back down to 650-700 between stop and go driving. Only would occur after the engine was fully warmed up. TP sensor was the fix for my issue.

 

[dodj]

I replaced my tps due to fluctuating rpms. I was not identical to your idle fluctuation, but similar. However, I could feel a slight surging occasionally at hwy speeds as well.
Make sure you clean the IAC on the bench, AND on a running engine.

 

[757speedaltcap]

Thank you all.

I recently purchased this Jeep and I am a brand new Jeep owner. Do you all feel decently confident this is not a major issue? It seems like all the suggestions are relatively small fixes. Just hoping for some comfort with a new purchase lol.

 

[Link]

TPS sounds possible. I was able to play your video. Do you have an actual code reader? Even better would be a code reader that can read live data. Then you can watch each input and look for anomalies. I suspect your PCM is setting a pending code so if so, you'll be able to read it with a decent code scanner. You should have your own scanner but you can also go to any auto parts store and have then read the codes along with any pending codes.