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Rough idle when cold and check engine light comes on

oldlegendoldlegend Member Posts: 1
My wife has a 2006 jeep liberty, 3.7L engine, auto 4X4. Has 40,000 miles. The problem is suddenly started having a rough idle at start up, and then the check engine light came on. We had a parts store check the codes and it came up random misfire. The check engine light blinked once, pause then 4 times and stays on, which is supposed to be the map sensor. I changed the plugs (gapped to .040) and changed the map sensor. Unplugged the battery for 10 min. and it started out ok. Then it had the rough idle again and the check engine light stays on, and again the engine light shows map sensor. So, any suggestions as to what the problem is and a solution for it. Thanks.


  • jakesunjakesun Member Posts: 1
    I recently purchased a 2006 jeep liberty. It's been at the dealer more then home. Check engine light on since the day after purchase. Foulded plugs,misfires and very rough idle. Turned out to be(so they say) a defect in one of the heads. Dealer did R & R the head. Have it back one week,check engine light on and rough idle. They now tell me it's a vacuum senser and not too worry about it.
    Think someone needs to come clean on the whole issue
  • fblack94fblack94 Member Posts: 1

    Any one of you guys figured out the problem? Just bought a Liberty Renegade 2006 and it started exhibiting these exact signs the next day...

  • suziestewsuziestew Member Posts: 1
    On 9/1 the day after an oil change and passing inspection, my jeep started to shake, check engine light came on, and when I stepped on the gas we went nowhere. Its now 12/16 and I still don't have my vehicle back. The PCM chip was replaced twice, after a tune up, it showed a misfire, the ABS module was replaced, the compressor on the A/C replaced,they ran it out of fuel to make sure the fuel pump was ok, and now its a complete engine tear down. I'm now told that the heads were sticking. Its an '06 and only has 43,000 miles on it. Anybody else having similar issues???? When I called Chrysler to open a file on this it was like talking to a machine..."and what is it that you would like us to do for you". I'm afraid to bring this jeep home.
  • Shelly422Shelly422 Member Posts: 1
    I have a 2005 Jeep Liberty 4x4 with an outrageous amt of miles but it was kept up nice And has a crap ton of new parts, new tranny, new this, new that. Anyway, check engine light came on... after running idle at a red light I went to gas it and went nowhere, engine rev’d up and then it finally kicked in and was fine until I get to work and it sits all day then on way home from work.... same thing happened. Mechanic put a new catalytic converter in it and surprise surprise.... on the way home from mechanic it was completely fine. This morning, on way to work, same thing happened but his time not as bad and engine light went off after the Jeep warmed up after a couple min. On way home from work, not running rough but Engine light came back on. At this point I’m over it and I’m taking my 2018 tax return and putting a down payment ON A HONDA and calling it a day. But until then I’m calling my mechanic on Monday morning bc I didn’t pay $1000 for basically nothing. Does anyone know what this could be so I can tell my mechanic very nicely that he’s fixing it “for free” this time? Any logical advice other then “it’s time to throw in the towel” would be greatly appreciated.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    Well hard to say what went on, since we don't have the details from the mechanic. It's possible he did fix one problem, but it might be a multi-problem fault. It would be good to know what codes are stored and also what test he did on the catalytic. With so many miles, catalytic do wear out.
  • MtndewdropsMtndewdrops Member Posts: 1

    Liberty KK owners, if you have a rough idle when cold that goes away when it warms up I found the problem to be O2 sensors. I was getting P0300 P0301 P0303 P0305 misfire codes . Very annoying. But it ran fine after warming up and I was getting 20mpg. I replaced the coils, plugs, wires, had the TB cleaned, injectors serviced all trying to diagnose this issue . I finally ordered 4 NTK sensors on eBay for $80 and had a local shop put them in and what do you know, it’s running great, no stumble or codes. Happy Jeeping 🏔

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