Stage 2 Sapphire 4x4 Cossie.

Guy says its started to hesitate and that it just gets worse if he keeps on driving.

On a testdrive today it went smooth while staying off boost, testet up to 6000 revs. While on boost I instantly heard a sound best descibed as a whisper and then a few seconds later a strong smell of petrol inside the car.

No hesitations or misfires so far but because of the petrol smell we did not want to test any further just to force a misfire.

Fuel pressure been setup with a mechanical gauge and the car went fine for a month or so after being setup with stage2 goodies. Tomorrow we will check it with my SPA gauge so that we can get an in-car reading while driving.

Any ideas what to check?
Car went smooth but that hissing/wispering noise was strange and the smell of petrol a bit scary. No visable leaks in the enginebay.

Also thought about removing injectors (only a month old) to check the spray pattern. Could an injector hold tight at standard fuel pressure but start leaking when the boost climbs even though the differential pressure stays the same?

The thing I can come up with to check that cause petrol smell:

Cause of hissing/whispering noise: