ramblin240

I have a 98 240sx with a 2002 Camaro LS1 + cam + dual valve springs and many other suspension and handling goodies.

Problem is, the car, when cranked up, sounds like there is severe scraping/knocking (no codes thrown) that is matched with the rpm even at idle. This just started yesterday and i have had what i believe is a very small coolant leak that I have yet to diagnose...I have checked:

- o2 sensors

- MAF

- Fuel Filter

- Air Filter

- Oil pump (oil getting to the top of the heads)

- Plugs

One thing i have yet to try is fuel pressure bc I dont have a gauge, but I will get one soon.

Anyone have any ideas? Thanks in advance!

00transamnh

iTrader: (1)

Are you sure the tune is where its supposed to be?

ramblin240

The tune has been good for 2+ years now so Im pretty sure. I drove it to work, it was fine, then I turned it on to go somewhere and I got this sound...

silverz28camaro

iTrader: (20)

did you check the rocker arms? make sure none are loose. maybe take a short video to and post it up to see if the noise is coming from the top end. maybe also check the flywheel torque converter/ or clutch bolts are all tight.

ramblin240

I checked that they were covered in oil as they should be in case my oil pump was goin out. Could it be the pushrods? The sound still remains when I put the clutch in.

silverz28camaro

iTrader: (20)

did you just look at the rockers or did you try to feel them by hand to make sure none cam lose of the needle bearings didn't go bad.

its going to be hard to help you pinpoint this without hearing the noise clearly.

ramblin240

Video comin soon.....

bovi

iTrader: (5)

Strange, lets see vid.

ramblin240

http://www.youtube.com/watch?v=X6yiJL1ztdk

wfs

That is the car running. Please listen to the crazy sound. I really think its a vacuum leak.

ramblin240

Fuel Pressure at 70 psi.

Im beginning to think my leak is in my brake booster b/c my brake fluid is unusually low and this seems like it could be a likely culprit given the age of the car.

Ideas?

silverz28camaro

iTrader: (20)

sounds like valve train to me but its still hard to tell by the video. I'd cheacl all rockers at top dead center, one cylinder at a time.

SikkyMFG

Sounds like a bad lifter, have heard this before. Very high pitch so that would put the source of the noise in the valve train and not rod or wrist pin.

ramblin240

I had thought about that too...man, there are so many things it could be! crap..

ramblin240

Gonna take off belts today and see how it runs for a few seconds...maybe its an accessory...

bovi

iTrader: (5)

Its always a pain in the *** to find something like this, but i'd say like sikky.

ramblin240

Takin the belt off didnt help.....

ramblin240

What about worn out lifters? Did anyone watch the video and think anything from it?

SikkyMFG

Sounds like a bad lifter, have heard this before. Very high pitch so that would put the source of the noise in the valve train and not rod or wrist pin.


listened again, I would put money on a collapsed lifter. Great opportunity to upgrade the valve train and install a new lifter set. Just my 2 cents.

ramblin240

So here's my next couple steps:

- Check oil pressure

- Pull lifters (any way to know they are bad other than diagnostically? test of some sort?)


Any more ideas?

TT632

iTrader: (3)

X2. If the wheel is siezing up it will have a screaching noise that is fairly continuious. check it out before you cause more damage