R33 - Strange Rattle Under Load.

[Killbot]

Hey guys

I've got a series 2 NA R33 and there is an odd rattle in the engine.

It only happens when the engine is warmed up, and only happens when the engine is under load i.e it doesn't happen when I'm in neutral or clutch is in. The harder i push the accelerator the louder it gets, it kinda sounds like someone is shaking a small spray can under the hood, really loud though.

Ive done some looking on the forums and its not the lifters, but it may be ticking injectors. Ive also had people say it might be some loose exhaust shielding or loose manifold but i don't particularly trust them. A mechanic said it would be fixed with a new catback but i reckon he doesn't know what he's on about either, but then again, what do i know

Just wondering if anybody has any ideas or has encountered this problem before.

cheers

[blind_elk]

If you had a turbo, I'd be suggesting detonation. I suppose it still could be.

It could also be piston slap - cylinder has gone a bit "oval", so piston doesn't "fit" properly.

[Killbot]

Yeah, still kicking myself for not getting the turbo. What am i looking at to get one of those problems fixed? Sounds nasty.

[DLOOOK]

As blind elk said ticking sound could indicate pinging/detonation. Try a higher octane fuel. Have you checked your timing? If it is pinging i would'nt be driving it hard until its sorted

[Killbot]

Higher octane fuel doesn't seem to change a thing, it still does it, but as i said its only when it really warms up. Haven't checked the timing yet, might give that a bash. cheers.