Testing if a Fuel Pump is Bad Volkswagen Passat (1998 – 2005)

By | October 26, 2023

Testing if a Fuel Pump is Good or Bad 2004 Volkswagen Passat (1998 thru 2005)
I have a friend who was having a fuel pump problem on a 2004 Passat, so I went over to help troubleshoot.

At first I was ready to simply swap in a new one until I seen the price, which would make it costly if it was not the problem.

Plus, a special tool is needed to push it in and out, so I wanted to be sure the fuel pump was bad before swapping in a new one.

After reading online in various forums, I found this can be done with a multi meter and another person to turn the car ignition.

Testing The Fuel Pump is a Two Step Process.

  • First, we want to be sure the correct voltage is being sent to the pump.
  • Second, we will test the fuel pump itself.

The first thing to do is get access to the fuel pump which is in the trunk. There are three screws to remove with a Phillips screw driver.
Testing if a Fuel Pump is Good or Bad 2004 Volkswagen Passat

Locate the Fuel Pump plug and remove it.
Fuel Pump Location Volkswagen Passat

The fuel pump needs to get the correct voltages, or it won’t work.

Pins 1 and 4 on the plug (outer pins) are tested with a multi meter set to DC voltage.
Fuel Pump is Good or Bad 2004 Volkswagen Passat

Another person will need to turn the key to accessory and the start position while you are watching the meter.
Volkswagen Passat Fuel Pump Wiring Voltage

This is what the voltages should read at the plug wiring harness.

  • With the key in accessory, it should read 3-4 volts DC.
  • When the car is cranked on and trying to start, it should read 11-12 volts DC.

If you do not get the above voltages than most likely a problem is in a fuse, relay, or in the wiring going to the fuel pump.

How to Test The Fuel Pump VW Passat (1998-2005)

The plug should be off the fuel pump and leads exposed.

Set a multi meter to read resistance (200 Ohms).
Volkswagen Passat Fuel Pump Testing if bad or good setting meter

Pins 1 and 4 on the fuel pump are the contacts to test resistance on.
Volkswagen Passat Fuel Pump Testing if bad pins 1 and 4

  • 0 resistance = Bad fuel pump
  • 1-3 ohms = Good fuel pump
  • High resistance = Bad fuel pump

Here is an example fuel pump that has just been replaced and is good reading 2.7 ohms.
Volkswagen Passat Fuel Pump Test 2004

Replacing The Fuel Pump In a VW Passat (1998-2005)

Replacing the fuel pump is not hugely difficult as long as you have the correct tools.

A special removal tool is supposed to be used with Volkswagen fuel pumps to remove them.

Here is the special tool on Amazon (Paid Affiliate Link)
Baum Tools 3307 Volkswagen and Audi Gas Fuel Pump Removal and Installation Wrench

I didn’t know a special tool was needed and only found out after the pump I ordered came in.

After playing with it for 2-3 hours hands covered in gas I finally got it in without the tool.

If I ever have to do it over, I would definitely order the tool as I did almost break it trying to get it in.

Bob Thomas
Latest posts by Bob Thomas (see all)

19 thoughts on “Testing if a Fuel Pump is Bad Volkswagen Passat (1998 – 2005)

  1. David Sursely

    Bob. Thank you! For making it fast and easy to understand. No life story’s no dramatics, no bull sht. Just the simple facts. Your awesome I hope you go far.

  2. Damith Prasana

    Woskwagen passat 2007 fuel pump control module
    What is the out put voltage to pump motor ?pls, reply me soon Damith.

  3. Topher

    I’m getting 1.3 to 2 ohm on the pum and 10.5V min on the plug is the voltage not enough to turn the pump on? it’s not priming

  4. Joe

    2001 vw beetle. Pump primes…butt no start. Will start with starting fluid. Pump tests ok…1.5 ohms. But not getting any voltage while cranking…relay?

  5. Roman

    Thanks mate. I changed my pump before changing my filter with a scrapyard fuel pump. It reads .6 ohms bad. And the og pump reads 1.5 good. Could it have been starved of fuel before cause of the filter? And I just burnt out the scrap yard pump? That’s my guess. I’ve changed the ecu relay, fuel pump relay, crank and cam sensors. New plugs as the ceramic cracked on on plug. There’s no more codes. I’m waiting on brand new engine speed sensor if it’s not the pump. Other wise maybe I shorted a wire between the fuel pump and ecu or the spark wires. But it does run on starter fluid so it kinda confirms all those systems are working correctly. Everything should work great as they did previously. It did act up a few nights before by not performing two step and nls. Maybe I’ve got a bad ground somewhere 🤷🏻‍♂️

  6. Enrico

    I have a VW rabbit 2,5 engine 2007 Canada model. The fuel pump making noise. The car esitate to start. What’s the pin resistance value for my model. Is it still from left to right pin number 1 and number 4? Thanks

  7. mark

    When I checked for DC Voltage from pin 1 and 4 on the cable that goes to the pump. Mine goes overload, What is the issue? I can’t figure it out.

  8. Ashlie

    Won’t start, but theres no juice or fuel even getting to the fuel pump 2001 passat

  9. Bill

    Very informative thank you, leads 1-4 reads 1.6 Oms you say above 1.3 is bad fuel pump so is this reading a bad fuel pump for sure?


  10. Dan

    Good write up. How has the bosch pump been for you? Im trying to decide between the bosch and the VW one. This one lasted 130k so the extra price may be worth it for the genuine part.

  11. Wade

    how high of resistance are we talking if the fuel pump is bad? My ohm meter is working as I tested on some other resistors and when I check the pump I’m getting like 1300 ohms. this seems super odd.


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