fuel starvation/loud pump on 83 urq (long)

Brady Moffatt bradym@sympatico.ca
Mon, 23 Jun 2003 19:13:55 -0400

Hi All,

A little history on this problem, and some things which may or may not be

Whenever the fuel gauge reads just into the reserve, I run out of gas. When
I refill the tank, I can put in no more than 75L. The pump clicks off and
the gauge reads full. The fuel tank appears to be new, but then again I
guess they age pretty well sitting there in the trunk.

The fuel pump has always been noisy, and it crackled sometimes. The
crackling went away after I cleaned up the connections and relayed it right
to battery power.

The car leans out at WOT over 4500RPM in 5th or 5000 or so in 4th. I see my
O2 voltage dropping away from 0.75-0.85 beyond  those engine speeds.

Yesterday, with a full tank from the day before, I'd see the O2 voltage go
down to 0 and at the same time the car would sputter and lurch with no
power. The fuel pump would also get louder and much higher-pitched than
usual. Once the pump returned to normal, if it did at all, the O2 would go
back up and the car would run normally off boost. I didn't dare try boost!

The louder higher-pitched pump noise could be duplicated by pinching either
the inlet or outlet hoses of the pump.

I'm thinking all these are related, and that something in the tank is
preventing fuel from getting pumped out.

Any other ideas?

Of course, I'll change the fuel filter and look for kinked hoses. I'll
probably end up draining the tank too. Figures, I just filled up with 94!

Brady Moffatt
Montreal, Quebec, Canada
83 UrQuattro with 54,000 miles
86 4ksq with 310,000km
86 4ksq parts car
72 Datsun 240Z with 180,000 miles
92 VW Golf with 200,000km FOR SALE
in middle stages of quattrosis accumulatus

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