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Thinking my fuel pump is going, but...

Joemakerman

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.... if it is the fuel pump, why would it idle fine in park and neutral?

Thanksgiving afternoon I went up to my girlfriend's to let the dogs out; she was out of town at her grandparents. On the way back at any stop light the engine would start surging back and forth, between about 300rpm to 1000rpm. If I was moving though, it ran fine. 2nd or 3rd light from her house, it stalled out. After that I'd shift into neutral and hold it to 1000rpm to keep it alive. Got home, and parked it for the day. Checked the throttle body: clean. Checked the distributor cap: perfectly fine. I had just replaced the spark plugs a few weeks ago, I made sure the wires were capped on properly: they were. Later that night I tried to start it and nothing. It's been sitting since today in which my Dad turned the ignition and I popped the tank a few times with a rubber mallet: she sprung to life! Idled just fine until I decided to take it for a spin and see how it reacts. As soon as I put it in drive, the engine started started going from 300 to 1000rpm just like before, and I can feel quite a loss in power. Sure enough after I drove around the block, I pulled in to my spot and let her sit: she stalled out. From prior knowledge and a little research I'm figuring it's the fuel pump.

But why would it idle just fine in park and neutral? Stays right at 1000rpm, even after shifting back from drive. Like I said as soon as I shift into D, R or any other gear it just doesn't like it.

Thanks.
 
Either the rubber hose in the tank split, or the pump would be my first thoughts. How full is it? When the tank is full the hose split problem seems to be less an issue than when it's low enough the hose isn't in fuel.

That hose splitting is so common anymore, I might even just drop the tank to look at it before even testing fuel pressure, and replace it in any case.

Got autozones out there? You can borrow their pressure test kit for "free" (refundable deposit) if you don't want to drop the tank as a guess.
 
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Sounds exactly like a bad, or going bad, tbi fuel pump to me. I've been there on my truck twice in one year :doah:.
 
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