3.9 ENGINE NOISE

YOOPER96 · #1 09-18-2007, 09:22 PM

Hello,
I did a search and did not find any answers that quite fit my problem. My 99 3.9 has a noise that sounds a lot like a diesel. It starts about 10 seconds after staring it, but goes away after it is fully warmed up. Not the ticking sound described elsewhere. My local wrench thinks it is "piston slap". Has anyone had or heard of this problem? What is the fix? Thanks in advance for any input.

jonnymagnum · #2 09-18-2007, 09:30 PM

ya, its just piston slap. theres no fixing it. aslong as it doesnt get too bad, you will be fine.

master tech · #3 09-18-2007, 09:33 PM

You need to isolate it, is the noise coming from the engine block, or the timing chain cover. andis the oil level full.

YOOPER96 · #4 09-18-2007, 10:34 PM

I guess I should mention that the timing chain and gears a nd the tensioner have been replaced. Tha tensioner was bad. I'am going to take it back to the garage on friday to see if he can isolate it. He is talking a possible tear down but I wanted to get some input from you guys before we went there.

YOOPER96 · #5 09-18-2007, 10:36 PM

Oh and it got a fresh oil change while it was there.

rred · #6 09-18-2007, 10:50 PM

i had a buddy with the same problem. he started using a K&N oil filter with a high quality synthetic and that took care of the knocking.

varsis · #7 09-19-2007, 12:53 AM

Could be a rocker arm that once it warms up the oil gets there. Try some engine tune from sea foam. Cleans out the gunk from your engine too

YOOPER96 · #8 10-07-2007, 10:32 PM

Here is an update on this. Noise is coming from the lower area. Engine is out and pan is coming off. Question is after fixing this, what if any upgrades would you guys recommend while the engine is apart? I was thinking new oil pump, maybe lifters if the top end has to come apart. But what kind/brand? Any other suggestions? May as well do it now. Thanks.

varsis · #9 10-08-2007, 08:10 PM

Roller Rockers!

jonnymagnum · #10 10-08-2007, 09:24 PM

Quote:

ORIGINAL: YOOPER96

Here is an update on this. Noise is coming from the lower area. Engine is out and pan is coming off. Question is after fixing this, what if any upgrades would you guys recommend while the engine is apart? I was thinking new oil pump, maybe lifters if the top end has to come apart. But what kind/brand? Any other suggestions? May as well do it now. Thanks.

since its only a 3.9. I would just put a new oil pump/water pump, timing chain. and anything else while your in there. but I wouldnt put any performance parts on it though.