"Knocking" noise coming from front of engine?!?!

[SS/GNX]

I havent driven my car in two months almost now because my knock sensor was going nuts even under normal driving. Yesterday, I let it warm all the way up to operating temperature and just sit there and idle, because it had been a couple weeks since I started it.

After letting it run for awhile, I noticed a noise, like a "knocking" or tapping coming from the front of the motor! I sounds like its near the waterpump, crank pulley, or that general area, but I cant be sure.

The belt tensioner is also making a little noise, but thats not the source of this noise.

I jacked the car up and was looking underneath while it was running, and still could not pinpoint the cause for the noise. The only thing I noticed was the crank pulley had a tiny bit of "whobble" but it could have been my imagination too. The crank pulley is poweder coated, so I was thinking maybe it has a high spot on it and isnt sitting right.

But this problem just started a couple months ago, I thought if it were the pulley, it would have been there all along. Unless its a little loose.

ANY THOUGHTS??? IM LOST!

 

[BlackBandit]

Check and make sure the pully is tight. Also, have you cut apart an oil filter to look for flakes? That would be a good thing to do. How fast is the knocking noise? Does it change under load? The more details you give the easier it will be. james

 

[Lee_Burough]

I had a similar noise once. I disengaged the serpentine belt and the noise was gone....It was the tensioner pulley.

 

[scottyb]

Are you sure it's not the cam sensor tapping?

 

[dan lephart]

tappy noise

My cam sensor was tapping. Sounded like a bad lifter. Same area as you describe... New cam sensor assembly solved the problem. :biggrin:

 

[SPOT MY 6]

Gary start by doing as BlackBandit suggested (cut filter open, and look at the oil and filter element for copper colored flakes). Do this before starting the car again to be safe.

Next, do as Lee suggested (take the belt off and run the motor). This will eliminate the alternator, tensioner, water pump, and power steering pump as being the source for the noise.

If you still hear the noise, try a different cam sensor. i have a spare you could try if you want.

And if you STILL hear the noise, pull the timing cover off and check the timing assembly and cam button, and also the oil pump (gears, shaft and cover).

That should cover just about everything on the front half of the motor.

 

[SS/GNX]

Thanks for the responses everyone...

Okay, poked around with it yesterday and took the belt off and started it.
Noise went away... didnt try and drive it around the block though to see if the knock went away cause I figured it would over heat fast as hell.

So this noise, at least, has got to be somewhere in the pulleys/ tensioner crap. Checked them all while belt was off and nothing really made any noise, but I know the tensioner is making noise, just not sure if its the cause of my problem.

Could be cam sensor, does kinda sounds like its coming from that direction, I did take the cap off and check to see if anything was loose and it wasnt.

I am going to pull the oil filter off and cut it open. Better to be safe than sorry, besides, its been like 500 miles, its time for an oil change! =)

Im really hoping this noise that went away when I took the belt off is the cause of my problem! I need a tensioner no matter what.

 

[SPOT MY 6]

Did you put the belt back on and start it to make sure the noise came back? Also, drive the car around the block with the belt off, you'll be fine. Just watch your water temp gauge. It will take you 5 minutes. I would do that first before digging through other stuff.