Engine Noise... Please help Diag.

[pcella84GN]

Ok, heres the deal.... I get a strange knock type sound that i've been trying to figure out. Its seems to be comming somewhere on Passenger side cyl 2 area. I used a stethscope dosnt appear to be comming from the valve covers (upper end)... I placed it on the cam sensor and i do here the noise from there, but as i place my head down under the car it seems to be more pronounced underneath. Heres the strange thing. When i get on it hard and pull it back in the drivway the noise seems to go away, but will reappear if a let it sit an idle.... Anyone have any ideas?

thanks
Paul

 

[Squid4life]

1. Check oil level
2. Crawl underneath with car running and check for cracks in exhaust
3. Check flywheel bolts
4. Pull pan and check rods

Anything vibrating/motor rocking making the DP or soemthing hit?

Keep us posted.
Squid

 

[pcella84GN]

i do have a small eshaust leak, but its not that noise... It's funny becuase i noticed it when i changed the oil (MOBIL 1) and put a longer oil filter oil level is good.... . It goes away as u give it gas, but will reappear at idle 750 rpm. Not a lifter noise, more sounds like a loose rocker... but dont here it at the valve covers. Could it be the oil pump?


ah yeah... I checked the torque converter bolts as well
i havnt pulled the oil pan yet.

thanks for the response.

paul
derry nh

 

[Squid4life]

What kind of oil pressure are you running with the M1? I don't like using synthetic, for the reason you stated. Seems too thin, makes a little more noise, and creates new leaks. Try some good ole straight 30 weight and see what noise you have, bet it'll be less.

Squid

 

[pcella84GN]

my oil pressure seems to be very high... driving around its 70psi @ idle its 40psi or so.... if its sits at idle for a while it will go down to 20psi. thats about it though. You think i should try 10w30? that might make my oil pressure higher. Synthetic is this, but i heard it was the best for these cars for the turbo. But i guess i will try it. is that what u use. 10w30?


thanks
Paul

 

[Pronto]

Ah, another NHerite. Recklessrob is from Derry. He hangs out at www.t6p.com
more than here. He works at service station and an engine builder. He may be able to help diagnois the noise.

 

[jimmymopower]

I had a similar problem on my car. The noise was cause by the baffle in the oil pan hitting the crank. Sounds scary, but not a huge deal. It usually happens after a oil pan gasket change, the pickup tube fits under the baffle, and if your not careful when you pull the pan you can tweak the baffle up enough for the crank to hit a little. A screwdriver on the oil pan should tell you if this is the problem... Or if you pull the pan off, look for a spot right on the edge of the baffle that has had the paint rubbed off of it.

 

[pcella84GN]

mmm, thats sounds interesting... I will check that out and get back to you.
I dont mean to sound stupid, but whats the baffle do?

Oh BTW.... I know Rob from Derry... he's a cool kid, he has helpt me out many times.


thanks
PAul

 

[Pronto]

Hope you get your issue solved. Rob has helped several of us. Good guy!

 

[jimmymopower]

As best I can figure, the baffle is there to keep the crank from splashing the oil away from the pickup on the pump. Thats just a guess, regardless I'd leave it there . Have you pulled the pan off recently? Its surprisingly easy to bend the baffle if you don't want to pull the pickup off the pump with the pan hanging down (its a pain). Hopefully its something simple like this. Although I have heard of wrist pins only making noise at idle, its pretty uncommon. If you suspect this, set the plug wire of the cyl in question up with a dummy plug grounded to the motor and start it. In theory, if the wrist pin has play in it, the reduced stress from not having combustion in the chamber will make the noise go away. Also, while I'm thinking about it, check and make sure your torque converter bolts are tight, they can make some strange noises if they loosen up.

 

[Tow Man]

Check all accessory bolts. A/C, Power Steering and so on. These engines tend to vibrate bolts loose if you don't check them periodically. My car sounded like it had a rod knock just after I bought it. It turned out to be that it had only one bolt left holding the A/C compressor on, the rest were gone!

Hope it's a simple fix. Good Luck!

 

[pcella84GN]

i checked for all loose bolts, and exhaust for any movement.... Is it possible a knock type sound comming from the oil pum???


thanks for everyones input

paul
Derry NH

 

[jimmymopower]

The oil pump is actually located in the lower passenger side of the timing cover, right where the oil filter and adapter screw in. I doubt that its making noise, if I recall your oil pressure looked pretty good... your downpipe isn't hitting the upper control arm is it? Does the noise get louder when its in reverse, or drive, or does it stay the same? The belt tensioners on these cars can make some funny knocking noises sometimes too. As goofy as it sounds, I would check the oil pan just in case, it definitely threw me off for a while. Keep pokin around with a screwdriver with your ear stuck to it, try and localize the noise and let us know.

 

[pcella84GN]

the noise appears to be less noicable under load, such as putting it in drive i dont hear it that much, out it back in Park or nuetral it reappears. I will check. Like i said before when i put a stethescope on the cam sensor i here it more there (knock type sound).. thats why i though it may be the oil pump, as i thought the cam sensor sits on the oil pump... i guess i gotta go put it up on a lift and check underneath. thanks guys

Paul
Derry NH

 

[jimmymopower]

Cam sensor does "sit" on the oil pump, if I remember correctly. Should have an oil pump drive that goes from the cam sensor to the oil pump. Does the car have a new timing chain, or is it original? I cant remember if that was in any prev posts :redface: ...)

 

[pcella84GN]

i believe its the original timming chain... but when i replaced the cam sensor i remember getting a glimpse of the timming chain appeared to be in great shape.

thanks
Paul

 

[soundguy]

a timing chain can look just fine. Usually still do when they're bad. They stretch longer than they started out as and sometimes will slap the cover depending on the gap between cover and chain.

 

[pcella84GN]

if it was a timming chain wouldn't the noise be louder under more acceleration?