When i start it up, i can hear a slight hissing from behind the engine and the revs drop straight to 700rpm (roughly) without it doing the warm up thing of revving over 1000 then dropiing when it's warm.

 

what could be hissing. this co incides with the stock boost guage not working anymore as well!

hmmmmm....

When i start it up, i can hear a slight hissing from behind the engine and the revs drop straight to 700rpm (roughly) without it doing the warm up thing of revving over 1000 then dropiing when it's warm.

 

what could be hissing. this co incides with the stock boost guage not working anymore as well!

hmmmmm....

 

you more than likely have a leak from the boost pipe,check driverside of the balance bar which it connects to,this will effect your idle check for leaks on the hose,or if your gauge has stopped working,check the hose has not become disconected

A snake stuck in the engine bay ?

thankyou greg...and also syed.

greg, i've sent an email to you regarding getting my 60k service done at your garage.

Will check the balance bar now. what does it look like?

bar across the back of the engine matey.

oh next to the manifold?

oh next to the manifold?

check the hose coming of the balance bar shown in pic,you may have to follow it back to check for leaks

 

no, that's all attached ok thanks for the image

will keep an ear out for where the hiss is coming from