Hi All,

My '01 has progressively been suffering from a loss of power and bad fuel economy. Now most recently I can hear loud hissing sound from the front near the intake manifold when starting cold (worse when in gear) and also accelerating (medium to hard acceleration). My code reader is pulling a P0172 code indicating system is running rich. My research seems to point to a leaking vacuum hose, but I was not able to locate source of the sound yet. Does this diagnostic sound right? If so, does someone have some pics/part number which I can look up to try to identify the culprit better?

Thanks a lot!
Anthony

 

check the intake tubing as well (ie trace from the turbo to the intercooler to the throttle body) - that's moving pressurized air so its more likely to hiss than a vacuum line. You can try misting as well. If there's gonna be something hard to spot, it would be a line going into the PCV system (ie under the intake manifold)

 

See the S shaped hose that starts in the red box and goes to the throttle body? That one likes to crack in half. Mine was hard and brittle and snapped like a twig.

 

Perfect guys! Thanks very much this was it. The car actually accelerates now too

 

Boom! Always love a happy ending. Props to Hudini for his camera work.