I have an oil pressure dependant noise that at startup,

• Goes away when the idiot light goes out
• Is longer in length and more often the longer the car sits
• But isn't there 100 percent of The time
• Slight rattle but not a loud bang
• Never comes back, no matter how hot or how long the car runs

Oil pressure cold is always 75+lbs
Hot at idle is 17-20 lbs
Hot at 3200 rpm = 50lbs
39000 miles
2006 gen1 JCW

The only thing that has changed recently is I used 0-30 Mobil 1 European formula, but the noise has only become noticeable the past couple weeks. Before that it was whatever the stealer had put in it. I bought it at 29000 miles in December.

Since it is so short in duration, and dependant on a long wait in between "tests" what should I look for to assess if its rod knock or lifter related?


Thanks
-Scott

 

Sounds like the timing chain tensioner to me

Also, try using M1 0W-40 instead of 30

 

I have replaced many timing chain tensioners lately so it's possible.