Fuel system diagnostic help.

[Joshua Van Tol]

>
>I looked at the ignition cable that I had replaced.  I actually unscrewed
>it from the metal socket.  It seems that it didn't have a very good
>contact because the insulation material was melting.  I cut the end of the
>cable off to expose some bare wire, and I tried as best as I could to
>screw it back in there.  At this point, the car did fairly well again for
>a while longer (I don't recall if I had the 4K cap, but I don't think
>so.)  Then it started to have problems again.  I pulled over and looked at
>the cable.  It was once again melted.  I cut it off again, and from here
>was able to drive all the way home.


I think the hot plug wire is a red herring. The symptoms you describe 
sound like a fuel starvation problem. Next time this happens, go open 
the fuel tank, and see if you get a huge whoosh of air going into the 
tank. Sometimes the vent lines get plugged up and cause a vacuum to 
form in the tank as fuel is pumped out. Or you could have a piece of 
debris in the tank, getting sucked up to the fuel pump screen. I've 
heard of celophane wrappers from cigarette packages finding their way 
into tanks, and I've seen rust do this on many occasions. Or it could 
be the infamous quattro fuel tank coating coming loose from the tank 
and plugging the screen. Search the archives for "fuel tank coating" 
and you'll probably turn up lots of info on this problem and the fix, 
which involves removing the screen on the pump, and changing your 
fuel filter more often.
-- 
Joshua Van Tol -- josh at spiny.com