Bisqueth

is there some clever german thingie that keeps the fuel pump from running if there's too much pressure built up in the tank? or was it a fluke?
87 5ktqa - boxerchipped, strapped, sprun, fuched and euroed

Kneale Brownson

If you get a whoosh when you open the fuel tank filler cap, your tank isn't ventilating through the carbon canister (#1) like it's supposed to, usually because the solenoid valve (#9) isn't working. The ECU may not allow ignition if the valve doesn't relieve pressure??? I don't know but it's a guess.

<img src="http://www.vagcat.com/p/B062/025050.png">

SteveAngry

Perhaps you have a hot start problem caused by leaky injectors or bad CPS/timing sensor and there was enough time for them to cool off before you discovered the gas cap off works?

BTW, I once had a similar situation where the car wouldn't start and I undid the gas cap for some reason and got it to start only to find my problem was a leaking rear fuel line...got any leaks back there?

Steve
Michigan

Mister Bally

Had this exact scenario in New York City with my 1980 VW Scirocco many moons ago. Whoosh sound was heard. Car started up as soon as I sat back into the driver's seat. Then it was Garden State, here we come!

It may have happened once or twice after that on a hot day &amp; long trip but not a constant problem so I never did anything about it.

Bisqueth

maybe 10 minutes. it may be leaky injectors, tho