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bpowa 07-30-2007 10:08 PM

I noticed rough idle after lift.
well the idle is not jumping around or anything. I just knowticed when it is at a stop the jeep shakes more.. like weak motor mounts etc..

what can it be after a lift?


Triple88a 07-30-2007 10:13 PM

What kid of lift did you do? Manual tranny vs automatic? Did you drop transfer case?

Maybe a vacume leak or something? Check around the manifold for some rubber piping that may have came off loose since from memory thats where you have to shuv in a wrench to unscrew the shocks. Give us some more info on your rig..

JeepCrawler98 07-30-2007 10:23 PM

What type of lift?

bpowa 07-30-2007 10:26 PM

it was a 2'' bb.. 05 x 4.0liter automatic.. no I did not have to drop the transfer case.. The idle is not actually rough.. it just feels as if the mounts are tweaked somehow..

make the rig vibrate at idle.. the rpm is in a still position.

do I have to drop the t-case? if so why?

JeepCrawler98 07-30-2007 10:35 PM

The only time you'd have to drop the t-case is if you'd get very high speed vibrations as you're driving (this is usually right after taking off from a stop); this would be because the angle on the driveshaft is too steep as a result of the lift.

As far as the rough idle - unless something got knocked loose or screwed up during the install I really don't see how the two could be related. The only thing I could think of is perhaps some stress in the bushings on the stock components? It's a very long shot - but try loosening all the bolts on the suspension (don't remove just loosen) then retightening them to relieve any stress.

Did you put new shocks in as well? Perhaps these are stiffer and don't allow the frame to shift just that teeny bit as the engine 'bumps around' a little bit at idle.

Your motor mounts/tranny mounts should be unaffected as you did not drop the transfer case.

bpowa 07-30-2007 10:41 PM

I found this link..

I might try a washer or 2. I doubt its thenew plugs I changed.. I used champion platinums.. gapped all the same .33

Triple88a 07-30-2007 10:51 PM

when you stop.. shift to neutral.. does it still shake or does it ease up?

JeepCrawler98 07-30-2007 10:54 PM

If you changed your plugs I would be first to blame that for a rougher idle than a spacer lift. That t'case drop shouldn't do anything unless your vibes are with the driveshaft turning.

Triple88a 07-30-2007 10:57 PM

^ 2x

bpowa 07-30-2007 11:48 PM


Originally Posted by Triple88a (Post 111782)
when you stop.. shift to neutral.. does it still shake or does it ease up?

I did that its the same thing.. like I said the idle says pretty constant..

I figures the lift might cause the yoke to stress a bit.. I was wrong.. I tried the transfer case idea.. still does it..

I took out ngk plugs.. I am always a big fan of them.. but when I went to the parts place they had none for the jeep.... I figure mopar uses champions..

Why did chrysler switched to ngk?
I checked 3 places and no one sells the plugs.. dont want to go to ythe dealer and pay tripple the price for them.

Triple88a 07-31-2007 12:04 AM

vacume leak on the manifold or the plugs.. throw the old plugs back in and hope for the best..

bpowa 07-31-2007 12:13 AM

I tossed the old plugs there are no vacuum leaks.

its not that bad just think it should not vibrate at all for a 05. I might try buying some ngk's.

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