Suzuki GSXR-1000 Fuel Pump Problem

When a Suzuki GSXR1000 struggles idling at lower RPMs even after fuel system maintenance and the fuel pressure gauge erratically goes up and down, could the fuel pump be the problem?

Partzilla's resident Suzuki motorcycle expert John Talley does live Q&As on our YouTube channel every Friday at 3pm Eastern. In this session, John answers a question from one of our viewers about a potential fuel pump problem with a Suzuki GSXR 1000 motorcycle.

Suzuki GSXR-1000 fuel pressure test

Suzuki GSX-R1000 Fuel Pump Repair

I have a GSXR1000 that’s struggling at idling at lower RPMs, at anything below 2000. Above that, it’s silky smooth. I cleaned the throttle bodies, injectors and the fuel tank pump and changed the strainer, but the problem still persists. The fuel pressure gauge is erratically going up and down. Is the fuel pump the problem?

John Talley: Typically, you’re correct. Most times a faulty fuel pump will let it idle, but it doesn’t want to deliver all the juice once it’s really under demand. Just at the lower RPMS? I’m beginning to think it’s not the fuel pump. I wonder if it’s your throttle position sensor. That would be what I would look at. If it got bumped, even a tad while you were working on it or you replaced it and it didn’t calibrate it again, it’s getting a false zero and probably trying to bring it down even further. And that could cause it to not want to run at a low RPM. So I would get away from the fuel delivery system and take a peek at the throttle position sensor and see if it’s measuring in range. Hook an OHM meter to it and it’ll probably have three pins. One’s got up to 5 volts of power on it and the other is basically a potentiometer, and you’ll want to run the throttle plates through their complete movement and do a high and low reading just using resistance. See what you end up with and compare it to the manual.