Fuel pump relay/fuel pump

Asked by MakeupMatt Feb 05, 2009 at 12:27 PM about the 1995 Chevrolet Astro

Question type: Maintenance & Repair

I have already checked/replaced the electrical connetions on the relay, fuseable link and fuel pump connections. When I turn the key to the "on" position the relay activates and the fuel pump turns on for about 5 seconds then turns off. I turned the key to the "off" position and back to the "on" position with no result. If I jolt the ignition switch and turn it back on, the relay and fuel pump will activate with the same 5 second result. Is this a problem with the ignition switch or is it a failing fuel pump drawing too much power and deactivating the relay? Please help.... Thanks.

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Seth-Tabitha answered 15 years ago

The fuel pump is only supposed to run for a few seconds at a time when you first turn the key. This is to "prime" the fuel system and prepare for starting. The fuel pump should not run again until the engine starts, or fuel pressure drops below a predetermined level. This "priming" should happen EVERY time you shut off the ignition and turn it back on. If jiggling the key has an effect on fuel pump operation, I suspect you have a faulty ignition switch. You can test this by swapping the fuel pump relay with another similar relay in the fuse box. On most cars, the horn relay will work for this purpose. If this does not change the symptoms, then the relay is probably not the cause. If the fuel pump was drawing excessive amperage, then you would probably see this as a blown fuse, rather than a relay that does not stay engaged.

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rhtuxman answered 11 years ago

How do you reset the fuel pump in a 1999 Chevrolet astro van? and where it is located? please help

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