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On 1 Nov 2001, at 10:53, jesse wrote: > As far as the hard hot starting goes, have you checked that your > check valve is maintaining fuel pressure after the car is turned off? > Maybe you are getting vapor lock due to lack of residual fuel > pressure. While this is a vapor/boiling problem, so it's similar, vapor lock is really an entirely different animal. Vapor lock happens on the suction side of a pump, when the pumped fluid gets hot so that the suction on it causes it to boil rather than get sucked into the pump. It is (was) common on older cars with the pumps on the engine mounted ABOVE the gas tank. Mounted this way, the pump had to suck gas uphill so that the pressure on the inlet side of the pump was always slightly less than atmospheric.This reduces the boiling point of the gas in that region. With hot underhood temps, the gas there would boil and the pump would only draw vapor, which was not enough to run the engine. On our, and all modern FI cars, the pump is located under (or in) the gas tank. The pump inlet pressure is always slightly positive, and the ambient temp is generally cool. The only way these pumps can suffer from vapor lock is if the screen or filter preceeding the pump is blocked, so in general this is not a problem that we ever have. - Jim Adney jadney@vwtype3.org Madison, WI 53711-3054 USA ------------------------------------------------------------------- Unsubscribe? mailto:type3-request@vwtype3.org, Subject: unsubscribe