Paul .G

Hey up,
two parts to this:

On my 03 JDM STi I have got a noise, only when cold, it sounds like it is coming from the front/top of the drivers side bank of cams. It sound like a chain timing belt catching on a cover. A pulsing rotating sound.
There is no loss in performance with this and as I said it is fine when warm. It only seems to do this after thet car is left overnight.

Second part:
How does the cold start/timing advance work on this model? I belive it is adjusted by oil presure? and the noise seems to be coming from this area?

Thanks,
Paul

johnnyroper

if it sounds like belt noise i would get it checked out last thing you want is it snapping.
from what you describe only happening when cold it could be the belt is slightly loose and slapping on the covers

DAVE-W

Cambelt tensioner maybe?

Dave

scooby raff

have subarus got hydraulic cam belt tensioners on

Paul .G

Thanks,
I don't think it is the belt tensioner as that's more in the centre bottom of the block this is more top left (by the cam pulley wheel)

Also I could have been a bit clearer on the second part, I am trying to find out how the Cam timing advance/retard works not ignition timing

KenS55STI

Paul

The AVCS on these cars is hydraulically operated and the amount of advance is controlled by the ecu. I don't believe this is affected by cold starting except that the oil will not flow as well as when warm so this may have some small impact (although I stand to be corrected on this).

If you are getting a noise from that area then you would be best getting it looked at or listened to by someone who can diagnose if there is a fault or not.

I have a 2001 jdm sti and I used to get a noise on cold start, I had the timing belt tensioner changed and it was worse, investigation revealed the new tensioner was faulty, so I'm now on the 3rd one.

I have noticed the engine sounds noisier from time to time in the morning if I have been driving it hard the night before, even though I allow it to run to cool down before switching off and oil temperatures are ok. My previous sti 4 did the same though so I don't let it worry me.

RAPTER59

iTrader: (4)

hey I know this is an old thread but did anything come of this? I have the exact same noise on my 06 jdm and was thinking it was something to with the avcs and info would be cool

cheers
chris

Paul .G

Hey up Cris,
Long time since posting on here!!

Yes I sussed it in the end, it was the cambelt guide



it was the one below this that had moved a bit so was catching on the belt, once warmed up it must have moved away from the belt so the noise stopped.

Good luck!

Paul.G