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fredmeister fredmeister is offline
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Join Date: Oct 2002
Location: Baltimore, MD, USA
Posts: 2,235
Took voltage readings at the front pump terminals after rewiring the front pump relay by separating it from the rear relay and adding an inline fuse. I left the rear relay wired to the fuse panel as it is since this fuse should be capable of supporting one fuel pump now. Wiring runs alot cooler fact it does not even get the fuse holder warm at all. Relays feel cooler as well.

Battery voltage 12.1 volts with car not running. Measured 10.6 volts at the pump terminals. Doesn't seem too badly out of order, did not measure at terminals with car running and alternator charging at 14 volts though.
The front pump body does not feel warm and it doesn't vibrate much, just is very noisy. The rear pump by contrast is so quiet you cannot hear it. Its running cause I felt it vibrating but did not get voltages off this pump.
Car runs for 1-2 minutes after intial start up fine. Then AF ratio meter goes off scale and it eventually stalls.
Am now in the process of draining over 10 gallons of fuel from the tank so I can replace the front pump.....this is fun.

Ordered a new Bosch 044 unit as per other post advice on increasing fuel flow, so maybe this is a good thing in the end considering the engine mods I have made.
This issue better be the front pump cause I am tapped out of ideas.

Any thoughts?

1979 930 Turbo....3.4L, 7.5to1 comp, SC cams, B&B intercooler, Snow Perf water/meth injection, Rarlyl8 headers, Garret GTX turbo, 36mm ported intakes, Innovate Auxbox/LM-1, custom Manually Adjustable wastegate housing (0.8-1.1bar),--running 0.7bar max
---"When you're racing it's life! Anything else either before or after, is just waiting"
Old 05-06-2013, 07:11 AM
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