Fuel Pump Won't Shut Off

Hey there, I have an '89 CSX with a bit of a problem. It's my daily driver, and I've never had this problem before. I got out of the car before, and it sounded like the fuel pump was still whirring. The lazy idiot in me just said "meh" and went inside. When I came out a few hours later, and forgotten about it, I realized that the pump was STILL going! I put the key in, jiggled it a little, took it back out, and nothing changed. Then I started the car and it didn't even take half a crank for it to start. I drove all the way home about 10 miles, and this could just be paranoia, but idle seemed a little bit less than usual. Once I got home I shut the car off, took the key out, and the pump was still going. In a bit of a rage/panic in the pouring rain, I pulled the fuel pump fuse and it shut off.

So what's wrong with my car guys? What should I check for? I think possibly, my ASD Relay may be stuck in the ON position, but this can be a long shot. Just wondering if you guys could help diagnose this, or have had similar problems.

Thanks everyone!

Get a multimeter and start testing. I'd start at the ASD relay.

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Originally Posted by tryingbe

Get a multimeter and start testing. I'd start at the ASD relay.

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That's where I would start too. It must be on, or there is a very interesting break in the Z1 circuit which is getting power from the battery somehow.

relay shorted ?.

Tap on the relay with a Snap On 15mm closed end wrench. Yes, it has to be Snap On to work:lol:

Unless I'm all wet, if it was the ASD relay, the car wouldn't shut off. It powers the fuel pump, ignition, and injectors all off the same circuit. Unless another circuit is killed and the ECU loses power... I'd check to see if you have power to the coil & injectors when the car is off.

Unless the car was modifies at some point, and has a separate power relay for the fuel pump. I did that when building the harness for my Scamp. I wanted the Walbro 255 lph pump on it's own circuit...