'11 Limited 5.7l v8, 25k miles - getting a rough idle.
Happens when cold or warmed up. 'almost' Normal idle if I put it in park or neutral but very rough when in drive stopped at a light etc. hovering around 600 rpm.
Any thoughts? Could it be bad gas? wrong octane gas? Been happening for about a month now - so about 4 or 5 tanks of gas.
This is my wife's daily driver and she is about to drive from Northern VA to Boston this weekend (yay - more miles!) - She normally uses 87 octane. Told her to at least try 89 or 93 for the weekend to see if it helps any.
The first thing I would do is throw some Techron injector cleaner in the tank.
Also, I think 30,000 miles is the interval for plug changes on the Hemi. You might need them a little sooner.
Thanks Bill_de - I was thinking plugs also, but didn't realize it would effect the idle like that and not the overall performance (unless i just didn't notice it!)
I found the OEM plugs online at Rock Auto for $3.42 plus shipping- 5% coupon = $3.78 each. A little better than the $5 each elsewhere.
This just happened to me, with the exception that the check engine light is now on and the mds is not working (no econ light). I have 26000 miles and the vehicle has been maintained every 3000 miles at the dealer sense the day I bought it.
Dealer could not find 'anything' wrong and advised to run 93 octane for about 1000 miles to clear up the idle "as these Hemi's prefer 93" (BS!). done just over 1000 miles using 93 octane and still getting low/rough idle! (~600rpm). Same gas as I use in my FX and it doesn't have any issues.
Just install the BT catch can and the PCV valve was 'wet'.
Is the Throttle Body possibly the culprit and needs cleaning? (if possible and how to?)
Throttle Body may be bad or needs to be clean. If your PVC was wet with oil the TB is got oil all over it too. I would get some TB cleaner spray some on a rag and wipe TB out or if you are handy take the TB off and clean it.
Just picked up the Jeep from dealer yesterday - they said the target idle is 624 - and when connected to the computer, mine was 624-635 - so no issues! However, vehicle still feels like it is idling just a little low. Guess nothing more to do with it. :-(
I have cleaned the TB and the MAF sensor (different 'cleaning' products) - not very dirty.
They did however fix the Drive to Neutral 'Clunk' issue - software TSB as well as a spacer plate and filter TSB on the transmission. This resolved the issue and also got me a fluid change! Also updated the software on the radio and changed out the driver seat cushion due to it cracking on the side.
After 6.5 years and 56K miles my V-8 has developed a similar rough idle, and almost wants to stall. It used to be extremely smooth at idle.
This seems to have started after I stopped using the Jeep for my daily commute to work. I have a fresh tank of gas, and am trying to rev it higher, but it is not back to smooth idling yet. I hope this helps the mechanic types help us diagnose this issue.
I can have the spark plugs changed early (scheduled for 64K miles). I don't have confidence that the dealer will be helpful.
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