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-   -   Rough Idle, flashing engine light (http://www.jeepgarage.org/f5/rough-idle-flashing-engine-light-17619.html)

05WKinPA 01-18-2011 09:02 AM

Rough Idle, flashing engine light
 
Has happened twice. Once about a month ago just before I had my transmission fluid and filters changed thinking it was due and could be causing my issue. Well it happened again this morning. Idling in traffic and RPM's drop way down...WK is running rough like it might stall...and the check engine light flashes on and off for about 10 seconds, then goes off and everything returns to normal. Has only happened when the Jeep is cold. Does this sound like a misfire? I changed the plugs about 5,000 miles ago, but maybe I didn't torque them down enough? Any ideas?

lll2for3lll 01-18-2011 10:15 AM

Re: Rough Idle, flashing engine light
 
Well normally I would say fuel system service but you're getting the light. Take it in if you can pull the code yourself. Might be the EGR valve which is a cheap fix.

2005JGC 01-18-2011 03:26 PM

Re: Rough Idle, flashing engine light
 
Yeah a flashing mil either indicates that your monitors have not run yet (key on engine off for like 10 seconds it will flash for another couple seconds)... OR that you are doing or capable of doing serious damage to your catalyitic converter (misfire).

Pull the code and that will hopefully tell you what cylinder(s) are misfiring, from there make sure the plug is tight on that cylinder, you can also swap injectors with another cylinder. A compression test is really worthless, but if you have access to a compressor and a leakdown tester that would be helpful in deturmining cylinder integrity and if it is leaking, where from.

05WKinPA 01-18-2011 04:22 PM

Re: Rough Idle, flashing engine light
 
Quote:

Originally Posted by 2005JGC (Post 337102)
Yeah a flashing mil either indicates that your monitors have not run yet (key on engine off for like 10 seconds it will flash for another couple seconds)... OR that you are doing or capable of doing serious damage to your catalyitic converter (misfire).

Pull the code and that will hopefully tell you what cylinder(s) are misfiring, from there make sure the plug is tight on that cylinder, you can also swap injectors with another cylinder. A compression test is really worthless, but if you have access to a compressor and a leakdown tester that would be helpful in deturmining cylinder integrity and if it is leaking, where from.

Thanks 2005JGC. My dealer is running a sale on an engine maintenance tune-up. It's only 99.00 for new plugs, timing and idle adjustment...I'm going to have them do the plugs because apparently I fail at doing it myself. I'm also going to ask them to pull the code and see what we find. I have the 2005 V6 that doesn't allow you to do the key trick for the code.

2005JGC 01-19-2011 02:29 AM

Re: Rough Idle, flashing engine light
 
just fyi your paying 99 bucks for sparkplugs installed ;) there is no timing or idle to adjust on these. But by throwing them in there they sure make you feel even better about the deal dont they ;) ha ha.

99 bucks is a pretty good deal from a shop, I dont know off the top of my head but my shop is probably in the 1.0 hr range which is 105 bucks plus sparkplugs.

TJXJWJ 01-19-2011 07:58 AM

Re: Rough Idle, flashing engine light
 
$99 is good for plugs installed...my wife's 06 did the same thing last summer. I changed the plugs and it eliminated the issue. Not sure why, and I did not see anything particularly wrong with the plugs I pulled out, but it cleared it up. Could have been a fluke, but it ran like absolute crap for 2 days and the code it threw was a misfire code.

05WKinPA 01-24-2011 10:21 AM

Re: Rough Idle, flashing engine light
 
Hey guys, just wanted to thank everyone for the helpful advice. I had the plugs changed on Thursday and put almost 1000 miles on the WK this weekend. No issues and it's running great.

Really appreciate the help that is available on this site!!

2005JGC 01-24-2011 03:20 PM

Re: Rough Idle, flashing engine light
 
glad that worked for you!


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