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How to test fuel pump?

Is there any way to test the fuel pump pressure without the pressure tester? 99 Camry 4cyl, I’m guessing fuel pump is bad, when I unscrewed the inline to fuel filter the line had no pressure at all. Does it already indicate bad fuel pump?

A quick check for a bad fuel pump is, remove the gas cap, and while listening down the fill tube, have someone turn the ignition switch to the run position so that the dash lights come on. The fuel pump should run for a second or two and then shut off. If you don’t hear this, there’s a problem in the fuel pump circuit.


You can measure how far the fuel sprays while holding your finger over the line. I think there is a chart in the Factory Service Manual as many mechanics cant afford gagues either.

No output either indicates the pump is not being powered up or the intake for the pump is clogged,or the tank is empty.

Are you testing for pressure using the correct key on sequence?

No, there is not a way to determine fuel pressure, anywhere accurately, without a pressure test gauge. For $35, anyone who is seriously troubleshooting a fuel pump will pay this moderate amount for a very serious piece of test gear. Example:

You can get an idea of the fuel pump output, at zero pressure, by disconnecting the fuel hose, place the hose end into a catch container, and powering the fuel pump for (say) 15 seconds. Measure the amount of fuel in the container. Multiply that figure (volume) by 4, and compare that figure to the specification table. has the specs. for your fuel pump of so many gph (gallons per hour). Divide that figure by 60 to get the spec figure for one minuet.[]
The fuel pump for your Camry output specification is 45 gph. This equals 3/4 gpm (gallon per minuet), or 24 ounces in 15 seconds.

To hot-wire the fuel pump, go to the Circuit Opening Relay and jumper the black/red wire to the blue/black wire. Jumper for 15 seconds while the fuel hose is aimed into a container. Remove jumper, and measure the fuel volume in the container. Compare to 24 ounces per minuet.

Thank you for you input. I have removed the fuel filter and with inline to filter exposed I turned on the key to “ON” position but new fuel came out. Should replace the fuel pump?

AS instructed you should see if the pump is getting the correct electrical signals that the tank has gas and that the pickup for the pump is not clogged.

Does the vehicle run on a priming product?

The fuel pump on your car is located under the back seat on the driver’s side. You can remove the seat by lifting up on the front of it. You might need to pry a little, but probably not.

With the seat out, you should be able to hear the fuel pump – which only comes on after the starter has been engaged. Of course, just hearing it doesn’t guarantee that it is producing adequate fuel pressure. You need a gauge to determine that, and a need a gauge that replaces the banjo bolt on top of the fuel filter because there is no Schraeder valve to connect a cheap gauge to.

Finally, if you decide you need to replace the fuel pump, you are likely to need a screw extractor to get the eight Phillips head screws that hold the access plate to the fuel tank. And once you get the miserable things out, you will find yourself confronted with a bunch of incredibly sticky black goo used to seal the opening. I’d put off going after the fuel pump as long as possible. And I’d replace those stupid Phllips head screws with hex head screws with the same length and thread when I reassembled the car.