Hoping for some help please. My mate has just picked up a jdm 96 wrx. It has a cone filter dump valve and a fmic. Apparently it has been mapped, but we don't know who by and apparently it is running 310bhp.
However, it is only running 0.5 bar boost (if the gauge is correct) it takes about 4 minutes to start from cold! But will start straight away when hot, but it idles at 2000 rpm cold and 1500 rpm hot.
Any info would be greatly appreciated,
Thanks paul.

 

If I were your mate, I'd get it to a specialist soonest, preferably BEFORE it goes bang.....

 

Definitely get it checked out or else there'll be an expensive repair required soon.

 

also do a fault code read and post list of fault codes (if any)
You can find how to do a fault code read by searching check engine light or CEL for a classic impreza.
Finally it may be that the idle control valve is gunked up..this can be rectified by the classic imprezas freind...brake cleaner!