secondending

this is my first post on ls1tech and i have all of the sudden had a noise that seems to originate from the top rear of the passenger side of the motor (02 camaro ss 54,000 mi). i dont drive it much except nice weekend days, which i know isn't the best thing for it, but now i'm not driving it at all due to the noise. when its first started the tapping seems faint but after the idle regulates it becomes louder. the tapping sounds as if the block or head is being tapped with a small hammer, but doesn't sound constantly loud, mainly after 1500-2500 rpm when it seems to peak. iv'e had a few mechanics over to listen but none of them think its a rod due to the volume and location of the sound towards the upper motor. and for whatever reason they also feel it isn't a lifter. iv'e removed the valve cover and the noise doesn't seem to be from the valve train. all rocker arms and push rods seem in order. when rpm's are up its not as loud but as it falls its louder until reaching idle where it fades some. even when trying to hold rpm's where its loudest the tapping isn't entirely constant and misses a few taps here and there. the noise doesn't sound frequent enough within the rpm's to seem that the rockers or valve train are the source, but raises and falls with rpm's. the car had a decent lift cam installed before i bought it and hasn't given an ounce of trouble in the 5+yrs. iv'e owned it. any help would be greatly appreciated as i'm trying to avoid tearing into the engine with fingers crossed that something surfaces. hope this makes sense; hard to explain.

thanks everyone.

crainholio

iTrader: (2)

What oil brand & weight, and what filter?

Disconnect the fuel injector for that cylinder, restart the engine, and see if the noise is reduced or eliminated.

secondending

i use mobil1 5w30 and fram extreme filter (same as used the entire 5+yrs. iv'e owned it). i cant tell which cylinder the noise is coming from but i could just start from the back and work forward to see if there any changes. will having a dead cylinder not create a rough idle that may disguise the sound? thanks for your reply.

crainholio

iTrader: (2)

Another case of valvetrain noise with SM/SN spec Mobil-1 5W-30. Hmm...

slammedc5

iTrader: (1)

Hum, I did my cam swap last month, just changed my oil last weekend. Now I have the tick. I HAD a Mobil 1 filter on there before, just had normal valvetrain noise. NOW I have a Wix on there. Ticktick tick.... Guess I'm going to have to swap the filter and see what happens

FL Junkie

iTrader: (23)

did you take the pushrod out and check if its bent?

OffspringZ28

iTrader: (8)

Check your spark plugs and exhaust manifold gaskets. If a spark plug is a little loose it will make a sound similar to what you're describing.