What is wrong ?

[Floyd9t8]

My WRX is making a sound from the engine area, it is a similar sound you hear when the your exhaust develops a 'blow', but it's not the exhaust. It is quite loud on start up then quietens a little, but only a little. Any ideas? 

[ven]

Not sure, but have you checked manifold/s ,possibly a fracture or around the turbo area.

 

How is it after a run..........better/worse,does noise get worse under load for example.

 

Any particulate side? maybe winding pass window down,then drivers to help which side whilst driving(just a thought)

[Floyd9t8]

You cannot hear it when you're inside the car with the door shut. It seems to be coming from the left hand section of the engine (so drivers side). No worse under load, starts loud then becomes a little quieter when the engine has been running for a few minutes. The car sounds as it should when you're stood behind it, but when you walk round to the engine area it sounds like the exhaust is blowing.

[savage bulldogs]

I'd guess at turbo to downpipe gasket or upipe .

Try jacking the front end up (safely) get someone to block the exhaust exit (bit of rag held over the end with their foot) and listen underneath and near the turbo outlet to see if you can pinpoint where it's coming from .

Don't run it for a long while blocked release the pressure every now and then just in case you make the blow worse with excessive back pressure

[Floyd9t8]

''I'd guess at turbo to downpipe gasket or upipe''

 

If that was the problem, what would the fix be? I am a little confused as to what exactly would be wrong if you're diagnosis is correct.

[Scoobyghost]

This is a picture of a gasket set I just bought. You would need the largest one in the centre of the picture for the turbo to downpipe join. Over time these gaskets deteriorate to a point that they break up and leave a small gap between the two metal joins. The bottom right almost triangle gasket is for the up pipe to turbo.

[savage bulldogs]

If the downpipes been removed at some point the gasket might not have been replaced with a genuine subaru one .

Same scenario for the upipe gasket and subaru exhaust system gaskets are "crush" type and ideally shouldn't be reused .

when they have they tend to blow when cold and blow a bit less once everything is hot and expanded

[Floyd9t8]

ScoobyGhost

Can I buy the relevant gaskets separately (if so where is the best place) if not where is best to get the set from?

Cheers.

[Scoobyghost]

You can buy them separately. I'm sure icp do the gaskets. I paid £13 for that set there and they're good quality. I had a look on eBay for my set.

[Floyd9t8]

Cheers Scooby I'll have a look.

[Floyd9t8]

Found the gaskets, any idea on how long it should take me.. is it a straight forward switch over?

[Scoobyghost]

The downpipe isn't the easiest section to attempt. It also depends if it's ever been removed before.

[savage bulldogs]

I'd visually check for soot marks on the joins once you've narrowed it down by ear.

As I wouldn't want you to buy gaskets that you might not need.

If it is a gasket issue and Pending in on the condition of the existing turbo outlet and up pipe studs and nuts, you might want to buy a few new ones just in case you fubar some on removal and have to wait until you can source some .

turbo outlet (once the tmic is off) 15 mins to change if all goes well.

Up pipe about 1hr and £20 for the swear tin