For a good 6 months now whenever I shut off my 92 xj 4.0HO there is a clicking/popping sound coming from under the valve cover, it almost sounds like popcorn.

It starts off pretty fast and then starts to slow down and comes to a stop after 30 seconds to a minute.

I've yet to have the ambition to pull the valve cover off since it only does it after I shut off the engine and otherwise it runs great with just over 200,800 miles.

Any thoughts on the cause?

 

No one?

 

interesting, i'll be suprised to find out...


sure it's under your valve cover? could be exhaust ticking and slows as it cools

 

Yep, valve cover. Doesn't seem to be heat related. I can start it up cold and shut it off after only running a few seconds and it still happens.

 

Did Orval Reddenbaucker own this Jeep before you?

 

It's possible lol. Almost makes me want to go out and buy a beater honda and fill it with popcorn to compare the sound. I'll try to upload a video later. It's the the oddest noise my jeep currently makes. As I said before it runs like a champ though with 200k miles.

 

" It's the the oddest noise my jeep currently makes."


haha

 

I know exactly what your on about! My 90' did the same exact thing. I pulled my valve cover off, looked for anything broken, missing, gunked up, etc. Couldn't find a damn thing. I even took a picture for reference. I cleaned off everything with parts cleaner and a tooth brush, put on a new gasket, and fired it up. Not a single difference. I never did figure it out.

But the motor would always start up, and never gave me an issue, and it saw some serious abuse.

 

Mine does the clicking too but I was always like that's weird... oh well

 

That doesn't sound like something I'd write off just because it "seems to run fine"... these are tough motors, there could be a serious problem and it's just dealing with it.. for now.

I'd get it looked at immediately if I were you.

 

that sound is your oil from the head draining back into the botom end

 

I used to have an odd sound when I shut off my xj over a year ago, and I haven't heard it since. It was coming from the same area you are talking about, but it sounded like a dull pop of a dent being pushed out of a pop bottle, and only did it once every time it was shut off.

 

Good to know I'm not the only one with this. This jeep sees a lot of abuse, I've put over 10k miles on it in the last 2 months.

 

A jeep that doesn't have a few odd sounds is a non running jeep.

 

X2