XBlack00FormulaX

2002 z28 longtubes, full exhaust and this sound. It comes and goes but lately has been doing it more http://www.youtube.com/watch?v=2RkN6xL2XeE

HottLS1Z

iTrader: (5)

Doesn't sound good. Did u make sure u didn't blow out part of a header gasket? Sounds like either that or maybe a stuck lifter or maybe a spun rod bearing to me. how many miles on it?

Sales4@Texas-Speed

iTrader: (4)

I would check the exhaust manifold gaskets because that sounds a lot like a header leak to me. It could be a lifter but it sounds pretty loud for it to be a lifter. I am not 100% on this because its a video though.

BennyB

iTrader: (12)

sounds like mine did. i changed the header gaskets only to find afterwards that i had a crack in my headers right where the flange met the primary. i could feel the air by hand coming from the back of the head on a cold start so i wouldnt burn myself

XBlack00FormulaX

car has 120k, 2 shops have said sticky lifter but its so loud so I really dont know

XBlack00FormulaX

I did put marvels in it about 4 days ago, nothing improved yet but was worth a shot

sidearmbandit

iTrader: (1)

You have yourself a broken/cracked flexplate. I have cracked 2 in my suburban. Sounds identical to mine. That is, assuming its an auto.......Get it up on a lift and pull the inspection plate on the bottom of the tranny. Shine a flashlight up in there and you should be able to tell if its cracked. Mine started out very minor and got worse. Once I finally figured out what it was it split all the way around the bolt holes.

XBlack00FormulaX

its a 6 speed , still could be the issue?

sidearmbandit

iTrader: (1)

You'll have to let someone else chime in on that then.....I would think you could crack flywheels in the 6 speed just like the flexplate in an auto but I'm not sure how frequent that happens. I just know it sounds identical to what mine did when it was cracked. I'll never forget that sound because it was on a brand new crate motor install with a new flexplate and new tranny. Made me sick when I had to drop the tranny back out after only 2k miles.

I would still look in that direction.....not sure if the t56 has an inspection plate or not. Definately an easy check to rule that out. Sounds much more than an exhaust leak in my opinion though.

XBlack00FormulaX

Cool thnx, had an exhaust shop check it and he said its in the motor when he was listening to it on the lift I wish it was though

sidearmbandit

iTrader: (1)

Here is what mine looked like when I pulled it off.....haha. The only thing holding it together was the torque converter.

XBlack00FormulaX

just got back from chevy a mechanic listened and said its a *leaky lifter* Is that even possible?

sidearmbandit

iTrader: (1)

Definately possible.......just sounds really loud for a lifter. Buy a cheap automotive stethescope (yep, like the doctors use) and hold it up to the valve covers, oil pan, side of the block. Anywhere you can touch while the engine is running. Once you hit the area where the noise is coming from, you won't be able to stand the ringing in your ear. Sounds funny, but I have diagnosed many of engine noises this way.

XBlack00FormulaX

had that done he stopped at towards the bottom of the engine right side then he said lifter

ae13291

iTrader: (8)

how is the oil pressure? is it needle twitching? you can remove the valve cover and try to determine which lifter it is.

XBlack00FormulaX

yep needle is twitching for sure but always sits halfway idle a little lower

ae13291

iTrader: (8)

yea its loosing internal pressure from somewhere. maybe a rod knock or lifter. somebody correct me if i am wrong but you can pull each one of the spark plug wires 1 by 1 to pinpoint it down to which cylinder it is for a rod knock

XBlack00FormulaX

is it ok to be even driving this car? It drives 100% no power loss or anything but I dont get crazy

PewterZCar

iTrader: (2)

Sounds like a lifter to me. After letting my car sit at idle for an extended period of time (when the oil pressure is at it's lowest) my car would develope the same sound. If I would take it out and drive it trying to increase the oil pressure the sound would go away. I fixed the problem by replacing the lifters.

If your car does the same, then I wouldn't hesitate to put in new lifters.

ae13291

iTrader: (8)

honestly i would not drive it like that not knowing what that sound is. if it is a rod knock you can blow a hole though your block if you continue to drive it.