Skip the auto shop - Our mechanics make house calls

Q: Car only runs when jumper the fuel pump

asked by on

The fuel pump in my car isn’t getting any volts. The following have been replaced in my car:

  • fuel pump
  • fuel pump basket
  • fuel pump driver module
  • fuel filter
  • starter

My car will only run if I jumper the fuel pump, since it hasn’t been getting any volts. Please give me advice on what to do to about the fuel pump. Thanks.

A: Check to see if you are getting power when ...

Check to see if you are getting power when you test the green with orange stripe wire going to the fuel pump module. If you have no power then check the the fuel inertia switch, in the left kick panel, by the drivers foot, and see if the inertia switch is not tripped. If it is, reset it and the pump should work.

If the switch is okay then make sure it has power to it and from it, when cranking the engine. If you have no power then check the fuel relay and see if it has power to it and that it’s being turned on when you crank it. If you do not then you may have an issue with the computer not activating the fuel pump. This will require a scan of the system and in-depth tests further than the scope of what this diagnoses is capable of. You will need a wiring diagram to follow and a scanner to activate the relays to test the system.

If you decide to get this fixed, contact a certified mechanic who can perform all of these checks in order to find the root of your starting problem. Once this is done, an accurate repair can be made.

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・Fair and transparent pricing

Get a quote

What others are asking

Q: I have a Mercedes 280 SL, 1985, WDB1070421A020760, many times it just stop while driving or at a stop. I have changed the fuel pump

Wow! A 280 SL with a manual gearbox is a rare machine indeed! It looks like you've eliminated a few of the prime suspects. The fuel pump relay would have been my first guess. But it looks like you've already...

Q: Fuel leaking from my engine.

You must have a fuel line that is leaking. Diesel engines have very high fuel pressure. With the age of your vehicle it is very possible that you have a fuel line that has rusted through. This is a pretty...

Q: does defective ball joint affect the operation of alternator?

Your ball joint will have nothing to do with the alternator at all. The ball joint is part of the lower control arm of the vehicles suspension and steering. The alternator is mounted on the engine and is used to...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
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.