Skip the auto shop - Our mechanics make house calls

Q: No power to the fuel pumps

asked by on

There is no power going to the fuel pumps. We changed all the relays over and still nothing. If we ground the wire at the plug for the computer where you connect an obd reader to we get the pumps to turn on. What would cause this problem

My car has 101000 miles.
My car has an automatic transmission.

A: This is a tricky issue to diagnose without ...

This is a tricky issue to diagnose without being there in person. It sounds like the pump may be getting a bad or weak ground. You will need a full wiring diagram and a knowledge of vehicle electronics and schematics to diagnose this. Start by checking power and ground for the pump at the relay terminals, and if you have power and ground, then jump the relay with a wire and see if the pump runs. If it doesn't, then it may be getting a weak ground somewhere else. Also check all the ground connections for the vehicle, especially ones along the frame of the truck, as these are often subjected to weather elements and may corrode, causing a bad connection. If this yields no results, I would have a qualified professional diagnose the loss of power at fuel pumps and help you move forward with repairs.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: No srart no crank

If you jump the starter solenoid on the fender from the small terminal to the cable to the battery then the starter should turn. If it turns then you may have a starter interrupt switch that is bad on the...

Q: Fuel

The Mazda 626 is known for having trouble with the fuel pump. Start by having the fuel pump checked to be sure it is getting continuous power. This can be done by simply turning the key on and listening for...

Q: power shuts down,but will run and drive very slow

For issues like this you should have the system computer scanned and have any codes diagnosed by a mechanic. The cost to have the problem properly diagnosed far out weighs throwing parts at the problem hoping to fix it. The...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.