alpinecarbon

Hi there
i have a newbe question about my uk 07 hawkeye wrx. My car has less than 10k miles and is standard powerwise.
It has a light 'tappety' noise from mainly drivers-side under bonnet which sounds a bit like a old vw beetle but quieter, this only happens below 3.5k rpm
under part throttle accelleration, noticable with window down in lower gears.
i thought it might be mild pre-ignition so i took it to subaru with warranty left, they checked and said the noise was normal for subaru's

I am used to nissan 200sx's and skylines, they are quiet and just purr under light load, so i am a little suspicious that maybe i should look for a leak on the manifold..

this isnt a big issue but i would really like to know if anyone else has this problem on theirs or maybe fixed this problem

alpinecarbon

update- i have been told this is likely to be waste-gate flutter due to a mis-adjusted lever/rod.
I will adjust this to try n get a light pre-load on the actuator with the car switched off and take it for a spin...

Splitpin

Who has told you that this is "wastegate flutter"? The actuators don't commonly come "mis-adjusted" from the factory and can't slacken in use. The spring might weaken a bit over several years' exposure to heat and pressure but on a car so new that's unlikely to be a factor.

It's notoriously difficult to diagnose "noises" over the internet but from what you've described a wastegate actuator issue would be far from the first thing I'd have guessed at. Have you actually had your fingers on the wastegate crank and can you actually pull it open or "waggle" it in the end of the actuator rod at the moment?

If not I'd put a small amount of money on the noise being caused elsewhere. If you do try this, be careful to note how much of an adjustment you're making so that you can put it back how it was if it doesn't make any difference.

alpinecarbon

hi splitpin, thanks for helping out. Ive tried to adjust the actuator rod and got stuck finding the last bolt on the heat shield and gave in, damn tight engine bay.
I took it back to subaru today and they were very helpful, but said all sounded normal and maybe its the resonance from the prodrive backbox! It would be nice to compare the sound with another hawkeye wrx because im starting to beleive that the sounds are normal. just seems to have quite a high pitched note to the exhaust at 2-3k revs,
your right its soo difficult to describe noises, doh!