Hello,
1990-245
Have had the buzzing fuel pump syndrome when less than 1/4 tank for months now so figured it was time to replace the intank pump or at least take it out for inspection.
Bought the IPD replacement kit anyways...

Took the pump out, put the new one in and thought I should test it out before closing it all up.
Jumped #4 and #6 and no buzzing from the pump, tried it with the key on and key off. Thought maybe I connected the wires backwards to the pump so I took it out and switched them still nothing (put the +/- back they way I think they should go). How do you know which is positive on the pump anyway? I just installed it the same look/layout as the old pump.

also following this procedure
http://cleanflametrap.com/transferPump.htm

- with #4 fuse out, engine off, key out, voltmeter connected to left side #4 and left side #6(fuse in) I have 12.9, with it running I have 13.5 so main pump has power. When I try to jump those two I get nothing going on at the main pump although my test light does light up, weird...

- With #4 fuse out and voltmeter connected to right side #4 and left side #6 I get no reading on meter, also when jumping I have no power or sound from the pump

Tried known good volvo fuel pump relay, no change to above tests, tried new aftermarket fuel pump relay no change. Tests were also done with o2 sensor plugs disconnected as indicated in link above.


any suggestions on where to look? The fuse box area is dry as can be, no leaks in the car, sender works fine.


Thanks
Gord
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1990 245, 1971 P1800e, 2007 C30 T5