Have a 1990 toyota extended cab pick up, 3.0 v6. As soon as I stick the key in the ignition, I can hear the fuel pump wine. I read a couple posts, disconnected the AFM, and the pump still ran as soon as I turn the key, and it keeps running. ...

If it's not the afm, where do I start??

 

Are you sure your key is actually off? I know in my truck, i can pull the key out before its actually in the off position. You can check easily by seeing if your radio or clock actually turns off. If your clock stays lit up with your key out, you need to depress the little button on top of your steering column, while turning your key backwards one more click. That should fully turn off the remaining power, which could be why your pump is running!

If its not that, I am not sure everyone who drives my truck never shuts it off all the way and I run into this alot.

 

If your key is really in the off position inserting the key will only cause the door buzzer to sound if the door is open.

If the fuel pump does start your truck is haunted!!

Then maybe one big electrical mess

 

As far as I know the vehicle is stock. And I also know the fuel pump is not supposed to run in the acc position, only w hen the vehicle is running, yet as soon as I shut of the engine I can still hear it wine, and yes...when I disconnected the afm wire and I still hear it, it may be haunted, but for real, would a bad fuel pump relay cause this?

 

There is no fuel pump relay, but there is a Circuit Opening Relay which is sorta the same. The circuit opening relay has two windings, one powered by the VAF when the engine is sucking air, the other powered by the key in the STArt position (not accessory, not ON, not with just the key in the keyway). When the COR closes it powers the fuel pump.

Do be sure the whine (wine?) you hear is the fuel pump; it pulls enough power to run the battery down in a few hours. Next, access the COR http://web.archive.org/web/201003261...96circuito.pdf and confirm that it is "clicking" (it's quiet; you might need a homemade stethoscope) when you turn the key to acc. If not, either have a bad (stuck closed) COR, or you have a short to 12v toward the pump. Then disconnect the COR and check for voltage on the STA pin. If you have voltage there with the key in acc you have a bad starter (key) switch.

 

All I can say is where you live must be very quiet

Do you need to disconnect your battery to keep it from going dead

Bad ignition switch Stuck Contacts on the Circuit opening Relay or the EFI Relay

I still go with haunted !!

 

Thanks Scope, I always look forward to your replys, Ill check out the link and test the COR.

 

So ...

Looks like the fuel pump has been tampered with by a previous owner. As there is a wire spliced in and running along frame directly to fuel pump, I will take the dash apart tomorrow and see where the wire is ran to. Just to confirm, the C ircut Open Relay is on the passenger side under glove box correct? Or is it the relay under driver side above brake pedal?

 

Passenger side.