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Do I have a weak fuel pump?

My pickup ('87 Toyota, 4 cylinders, 5-speed manual, longbed, carbureted) seems to have lost a lot of power. The compression tests to spec. The plugs and cables look

good and are relatively new. It passed the smog test in January.



It’s particularly bad uphill. I was on a steep road in the mountains and couldn’t get up the steepest bit: no fuel got to the carburetor. I backed down, got a running

start, and got up. I had filled the tank 30 miles before.



How can I test my fuel pump?

This could be caused by an old clogged fuel filter, or the screen in the gas tank could be clogged as well. If you test the fuel pump you need to check it for pressure, and also for flow volume.

My guess is the pump is generating enough pressure, evidenced by the truck runs fine at idle and under light load. When you are having problems the motor is under heavy load and needs more gas than it is getting.

Finding and replacing the fuel filter should be relatively easy. Cleaning the screen in the gas tank can be tricky. I’d have a mechanic run the checks on the fuel pump if a new filter doesn’t cure your problem.