2002 Ford Taurus with the 3.0L Vulcan engine. Car runs fine most of the time but after a long drive, park for 20 minutes or so and upon re-start it runs terrible for a few minutes then recovers to run normally. Recovers faster if you race the engine. Doesn't throw any codes. After much internet reading, my conclusion is it's a vapor lock problem with the fuel vaporizing inside the fuel rail. I'm guessing there's a leak somewhere in the fuel system allowing the pressure to drop which would lower the boiling point, maybe a leaky injector? Question is how to troubleshoot this? I can put a pressure gauge on the fuel rail and see how long it holds pressure but what should that look like?
This is a return less fuel system so any vapor that forms has to be passed through the injectors, right? We've been running ARCO gas so we'll try a brand name fuel to see if that helps, perhaps the boiling point will be a bit higher than ARCO who like to use a lot of ethanol! Seems like these Fords are kind of famous for this problem and people throw a lot of parts at it without solving the problem...
This is a return less fuel system so any vapor that forms has to be passed through the injectors, right? We've been running ARCO gas so we'll try a brand name fuel to see if that helps, perhaps the boiling point will be a bit higher than ARCO who like to use a lot of ethanol! Seems like these Fords are kind of famous for this problem and people throw a lot of parts at it without solving the problem...