Grating noise [Archive] - SXOC Bulletin Board

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PB_S14

23-05-2001, 09:31

Hi all. Have we all settled into our nice new home?

I've developed a horrible grating noise at the top of my engine.

Scenario: Rev the engine slightly, it drops down to 1000rpm, holds and makes this horrible grating noise for about 1-5 seconds, then drops to idle at 800rpm.

Had it into the garage, he says he'll have to book it in and stip the top to have a look. Reckons it's a camshaft problem, possibly the camshaft tensioner.

Thing that bothers me is there's only 16K on the clock. Should this be happening on a nearly new engine? Mechanic said S14s do have camshaft problems and these can show at any time. Is this true?

Any opinions?

Paul

Chimp

23-05-2001, 14:50

Im straying away from my S13 home here, but if its a proper loud grating noise and comes and goes with the revs, it would be worth while checking any heat shield mountings on the exhaust manifold. I got caught out with this once before( not on a nissan though), I assumed the cam chain was about to snap and I took it off the road for a few days, turned out as the engine was revving the heat shield was vibrating against the manifold. Its just a thought, and very simple to check. Do mind your fingers though, skin grafts do not a good time make. http://300zx.co.uk/200sx/ubb/smile.gif

I think the idle holding at 1000 then dropping to 800 might be unrelated to the prob, that sounds perfectly normal to me. Or maybe mines shagged too. :P

Tom_S14

23-05-2001, 15:08

Yeah, I'm sure the idle speed thing is quite normal. Mine definitely does it. I can tell from my MDM-100 gadget it seems to "decide" to idle based on the throttle position, revs etc.. there's actually an idle "software switch" setting on the ECU in a simillar way to the power steering and AC "switches" and seems to go into a different mode - probably to keep a tighter control on the emissions ?
I had a grating noise which turned out to be a heat sheild nearer the CAT under the car, early S14s suffered from timing chain rattle, they bought out a new tensioner design which I would hope is fitted as standard to new cars. It could be it needs adjusting ?
Tom

PB_S14

23-05-2001, 15:25

Yep. I know the idling thing isn't a problem, it's always that. It's just the new horrible noise going with it. Definitely coming from under the rocker cover somewhere.

Brucemc

29-05-2001, 07:23

Is yours a model with vvt? I have heard of quite a few with rattling problems due to this, and think was a recall in the US .
Try to get in under warranty as i have also heard its expensive.

Bruce

Brucemc

29-05-2001, 07:24

Sorry my connection stuffed up

[This message has been edited by Brucemc (edited 29-05-2001).]

Brucemc

29-05-2001, 07:24