3.6L Cold Start Valve Tap-Normal Or A Problem?

[DavidArmen]

My 2021 JLUR 3.6etorque sounds pretty much like that during cold starts. Noise completely disappears in a few minutes once it warms up. I only drive it a couple of times a week at the most so it sits for days all the time. Haven’t had it checked out yet because it’s been there since day one (8miles when I bought it, almost 10k miles now) and I’m not sure if it’s a big problem yet. Also, the fact it disappears tells me it might have something to do with the VVT/VVL adjusting once the temps reach operating range. But what do I know.

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[DavidArmen]

Here’s what mine sounds like with phone in passenger fender well

 

[JL2000]

Here’s what mine sounds like with phone in passenger fender well

Sounds like mine! Lol. What weird is I don’t recall hearing it during the first 4 months of having it unlike you who noticed it since day 1. I also drive my JL maybe once a week as I have a Jetta for daily driving. But I’m thinking; is it possible that maybe after sitting for several days it is enough time for the oil to drain back down to the pan and it takes a while for the lifters to get pumped up fully with oil again? Kind of strange though because none of my other vehicles have done this. Hopefully its nothing so we both don’t have to worry about it!

 

[JL2000]

It is your throw out bearing. Next time push in the clutch and see if it goes away. If so cancel your dealer appt because you won’t like their answer.

I will try that next time it happens, but I had a throwout bearing make a racket on my c4 corvette last year and it sounded quite a bit different and was every time I sat in neutral. But I will try it just to double check.

 

[stumblinhorse]

I will try that next time it happens, but I had a throwout bearing make a racket on my c4 corvette last year and it sounded quite a bit different and was every time I sat in neutral. But I will try it just to double check.

It is def your throw out bearing…. It is a very cheap part and it is not “failing“. That is why is sounds different from your C4 corvette. Your dealership will charge you $2k to fix the noise for a year or so. Leave it and forget about it till you need a new clutch.

 

[zakaron]

My first thought after listening to the video is valve train related, like ticking lifters that aren’t pressurized. To me a throwout bearing would be more of a whirring or grinding noise, not ticking or tapping. Please don’t be offended for me asking, but how is the engine oil level? If it’s low, that could lead to increased valvetrain chatter.

 

[JL2000]

My first thought after listening to the video is valve train related, like ticking lifters that aren’t pressurized. To me a throwout bearing would be more of a whirring or grinding noise, not ticking or tapping. Please don’t be offended for me asking, but how is the engine oil level? If it’s low, that could lead to increased valvetrain chatter.

No offense taken at all! I appreciate all the responses and different perspectives. The first time I heard the noise which was just after new years day, I immediately checked the oil and it was perfect. I will admit I have not checked it since, because I’ve put maybe 200 miles on since then.

 

[JL2000]

Somewhat of an update: Took JL into dealer on Thursday 2/10 for the noise. Service advisor claimed they heard the noise but by the time they got it in the shop it stopped. They wanted to let it sit over the weekend until Monday 2/14 to see if it’ll do it again. Monday comes and goes, don’t hear from dealer. I call them today 2/15 for an update, an am told it did not make any unusual noise upon startup, but that it was a quart low on oil. Service advisor stated that even with it being a quart low it shouldn’t have made the noise, which I agree with. Wasn’t told what they plan to do next but it is still at the shop, kind of irritated no loaner was provided lol, but kind of expected in today’s car shortage.

 

[JL2000]

Final update: Picked Jeep up today 2/17. Dealer could not get noise to replicate, and weren’t concerned over a quart of oil vanishing in 1500 miles. Guess I’ll just drive it more often for now and see if it acts up again

 

[DavidArmen]

Final update: Picked Jeep up today 2/17. Dealer could not get noise to replicate, and weren’t concerned over a quart of oil vanishing in 1500 miles. Guess I’ll just drive it more often for now and see if it acts up again

It’s possible that they think there’s a quart missing because they think the JL needs 6 quarts instead of five

 

[DavidArmen]

Sounds like mine! Lol. What weird is I don’t recall hearing it during the first 4 months of having it unlike you who noticed it since day 1. I also drive my JL maybe once a week as I have a Jetta for daily driving. But I’m thinking; is it possible that maybe after sitting for several days it is enough time for the oil to drain back down to the pan and it takes a while for the lifters to get pumped up fully with oil again? Kind of strange though because none of my other vehicles have done this. Hopefully its nothing so we both don’t have to worry about it!

A few days is definitely more than enough time for the oil to drain down to the pan but it shouldn’t take more than a couple of seconds for the oil to get sprayed all over the cams and other areas on the top of the engine once you start up the Jeep.

 

[DUNE RAP]

Any further updates on your Jeep Sir?

 

[JL2000]

Any further updates on your Jeep Sir?

I wish but sadly no. Jeep still continues to make the noise pretty much randomly at start up. Sometimes it is for a short while, some times for 10 mins, sometimes the engine is as quiet as can be. The video link to youtube is a clip from the end of Feb. and led to me scheduling a second appointment at the dealer, to which again they found nothing.

 

[SouthernJL]

I just came across this old thread. I was out of town for a week. We took my wife's car so the Jeep sat the whole week. This morning when I started my 21 JLU 3.6 to head to work, it idled pretty high for a few seconds like it always does on cold starts after sitting for a couple days. But what was new was the loud ticking.

It's rare that my Jeep sits a week without being started. As a matter of fact, I don't think it's sat that long ever in at least the last year or so. After returning from work this evening and letting the Jeep sit a couple hrs, I restarted it again. No ticking.

I've read about the rocker/lifter ticking thing and how it's a common fail on the 3.6. My question is, is the ticking common or expected after the Jeep sits several days? Or does this indicate an issue and I need to schedule an appt to have it checked out?

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