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Jeep Liberty Engine Noise

2005 Jeep Liberty started making a clack clack clack noise one morning, but quit after a few minutes. About a month later, upon starting, it started clacking again, but didn’t go away. Jeep dealer mechanic looked and told me it’s probably a valve lifter or something in same area. But when I took it to the dealer by my house (after noise got worse and engine light flashed, decreased power) he said they go a generic “misfire” code, so he says it’s spark plugs (only has 29k miles) and not covered under warranty and wants $980 to to tune up. Help!

I doubt that a $980 tuneup exists in this day and age. Take your little Jeep to a good independent mechanic and find out what the real problem is. Stay away from the dealerships because I think the one you went to just wants to rip you off. That mechanic is a would be thief in my opinion.

Yep – I agree normally, but because it would be under warranty if it really is a valve lifter or something like that I would only be able to get the work done at a Jeep dealer. And now it’s been towed there. I’d likely have to get it towed to somewhere else and pay full price for some warranty work. Any clue what the real problem could be?
And if the misfire code only comes up when/if the engine light comes on?

The code is stored in the computer regardless if the light is on or off. Most warranty work can be done at other shops as long as it’s completely documented. I would check at a couple of places.

Engine light never came on until today – before it was just clacking sound. Wondering if it started misfiring because of sticky lifters, etc. — meaning that the cause is not spark plugs. I also asked a local mechanic and they said they couldn’t do warranty work. And I’ve got no references for any other places – haven’t been here long and have’t had any work done here before.

There will be a miss if the valve is not operating correctly. Spark plugs do not control the valves so I don’t think that’s the problem. The Liberty uses a DOHC 4 cylinder and a SOHC 6 cylinder. This means that something is probably wrong in the valvetrain if there is a “clacking” noise. The engine valve cover will have to be removed to see what’s wrong. Hopefully, it’s just a hydraulic lash adjuster.

Thanks for your help! They said that they opened the valve cover and that the engine all worked perfectly – but I have doubts they did that, especialy since they called me 3 hours after I dropped it off and just told me to have the 30k maintenance done (plugs) + a MAP sensor which seems to be working fine. I will go in person today and ask them to show me why they think a plug is bad. I’ve been told by others that you can check the gap, etc – not just by reading a misfire code.

Do You Have A 3.7L Engine ?

There is a Chrysler TSB (Technical Service Bulletin) for Jeep technicians that discusses “engine misfire at idle” which may illuminte the the MIL for single or multiple cylinder misfires.

It doesn’t mention anything about a “clack, clack, clack” noise.

The bulletin covers 3.7L 2005-2006 Dakota (ND) & Liberty/Cherokee (KJ)(International Markets) vehicles. I’m not sure if that’s your’s.

The fix is the installation of revised intake valve locks and intake valves, requiring cylinder head removal.

I just thought I’d throw this in. You might want to check it to see if it applies to your situation.

CSA

YES!! I have heard a little about this TSB – but couldn’t get much info. It started with the clacking sound (so I was told it was likely a valve lifter, etc – and it was a Jeep tech who told me about the TSB after he heard the noise!) The only symptom was that clack noise – until I was on my way to the service dept to get this supposedly under warranty problem repaired. On the drive there my engine light then started to come on — presumably that’s when the misfires occured? Would this valve problem make the misfire code appear? And could a bad spark plug (at only 29k miles) really make this clacking sound (like they’re trying to tell me now – NOT under warranty and big $$)

Originally there was just a “clacking” sound. Could that have been a spark plug issue? It only has 29k miles … but since that’s something you’re supposed to replace at 30k I think that’s why they are trying to take the lazy way out – and make me pay vs being a warranty item. And only indicator they can give me for diagnosis is generic misfire code (P0300) – which may have only occured because my engine light came on during the drive there.
If it IS something related to the valves, would this eventually cause the engine to misfire?

You Ask, “Would this valve problem make the misfire code appear?”

In my last posting I indicated that the TSB discusses" . . . ‘engine misfire at idle’ which may illuminate the the MIL for single or multiple cylinder misfires."

The “MIL” they’re referring to is your “Check Engine Light”. MIL = Malfunction Indicator Light.

So, Yes. If you fit this description then check into it with a technician like the one who told you about the TSB.

CSA

Thanks for your input! I went back to the dealer again today (which is where I took it when because I was originally told it would be under warranty) ? and the story has changed again. I asked a million questions. Now they?re saying that the MAP sensor is bad (baro reading at 31.3 should be at 30.3)?and that they caused the spark plugs to go bad. I did see two spark plugs (can only assume they?re really from my jeep) ? and they did look heavily fouled. So ? I unhappily agreed to have them replace the spark plugs (because they obviously need it now) for $185 and the MAP sensor (which they say the car will not run unless I replace this part ? not sure I believe that) for another $150 or so?.

I said that if it turns out that the probably actually started from the thing in the TSB would they refund the cost of these repairs since they were caused by the thing under warranty. He said the sensor and plugs would be ?collateral damage? and not covered. I told him that I would be happy to take up the matter with the Jeep arbitrator if this turns out to be the case. (And I?m suspicious that I?ve been quoted prices from $980 all the way down to $185 to fix this problem — or it could be covered by warranty — and I?ve heard various diagnoses from the same people!!)

In the meantime I guess I?ll wait for them to call me this afternoon and tell me if the plugs and sensor were the problem. I hope that?s all it is?. but I?m a little pessimistic after everything I?ve heard from you and other Jeep mechanics!

AHA! You were all totally right! Thanks to CSA and Missileman for their input. I just got a call from the service manager. He did replace the plugs and sensor ? and it is still going clang clang clang!! I had to say I told you so!! So, they will tear the engine apart and it should be covered under warranty. However, he says that the work they already did (plugs, sensor) will NOT be covered. And even if the damage to them is ?collateral damage? from the real cause of the clanging, collateral damage is not covered. I told him I would take it up with Jeep mediation team if necessary once he finds out what the real issue is.
So ---- if it?s really the same as the TSB discusses ? or a valve problem, etc ? could/would that have caused the misfire, thereby wearing out the spark plugs and/or sensor? If so, I?ll definitely fight it.
Thanks so much for all your input!!

first clue, overhead cam engines do not have lifters. clacking could be due to bad timing, or if the adjustment nut on the rocker arm came loose, or if a tooth broke on the timing chain, or if a bearing on a water pump or alternator has a cracked roller or ball, or …