fuel pump voltage
Thread Starter
Burning Brakes
Joined: Jun 2002
Posts: 838
Likes: 0
From: Redding CA
fuel pump voltage
Hi Again, lost my fuel pump tonight. Left the house and before I got on to the main highway she started sputtering, fired right up probably drove 1/4mile before the fuel in the system ran out, had to push her about half a block, glad it was 10:30pm all my neigbors were inside. Anyway while I was trying to determine if it was the fuel pump I noticed that the wires that go to the fuel pump only showed 10.81VDC, is that normal? I am sure the pump is bad, I checked it out of the tank direct to a battery. What I am wondering is if the low voltage might have caused the pump to go bad. It is less than 2 months old. Also it is a bosch high flow, new strainer,filter,fpr,pulsater.TIA :cheers:
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: fuel pump voltage (kabnvtt)
10.8 volts won't do any harm to your fuel pump, only its delivery rate which will still be in excess of engine requirements. What is the battery voltage at the battery terminals? If it is also 10.8 volts, then your alternator isn't charging the battery and this low voltage can cause your C4 to quit running. If the alternator isn't charging, then the red battery symbol light should have come on. A car battery is considered discharged when its terminal volts fall to 12.0 or below. Fully charged it will be 13.2 volts.
[Modified by jfb, 10:11 AM 8/4/2002]
[Modified by jfb, 10:11 AM 8/4/2002]
Thread Starter
Burning Brakes
Joined: Jun 2002
Posts: 838
Likes: 0
From: Redding CA
Re: fuel pump voltage (kabnvtt)
Yeah that is what I thought at first but I made sure that it was charging.Not sure what the voltage is while it is running , have no way to test rigt now, have to go find a fuel pump. :cheers:
Team Owner
Joined: Jul 2002
Posts: 22,267
Likes: 15
From: The light that never warms.
St. Jude Donor '12
Re: fuel pump voltage (jfb)
Check your fuel pump relay while you're at it. It's on the firewall next to the brake booster. It's not uncommon for the relay to go bad.
Thread Starter
Burning Brakes
Joined: Jun 2002
Posts: 838
Likes: 0
From: Redding CA
Re: fuel pump voltage (lite blue)
got the new pump in, car runs great. 42psi. voltage still around 10.81VDC,guess we will see if this one quits if so I will look for the lower voltage? :)
Burning Brakes
Joined: Feb 2000
Posts: 824
Likes: 2
From: Camden SC
Re: fuel pump voltage (kabnvtt)
You may consider changing the fuel filter when changing the pump. Partially clogged fuel filters contribute to premature pump failure. The pump is drawing more amps, pushing fuel through the filter and over time, will cause failure. One shop I know of always replaces the fuel filter when changing the pump. This assumes you didn't replace the filter last week. One other point, getting really low on gas, or even running completely dry, is not good for the pump, or ones ego.
Glad your car is fixed.
dlmeyers 90 coupe zf6 3 speed shocks
Glad your car is fixed.
dlmeyers 90 coupe zf6 3 speed shocks
