fuel pump problem
#1
fuel pump problem
So I have a 2wd 93 22re and it wouldint start today. Traced it down to the fuel pump wiring. It will run with the fp and B jumped. But as soon as I pull it out the engine dies. I tried a different fuel pump relay and nothing changed. Also with The key in the on position I pushed the afm flap and I can hear the relay click but the pump wont run. Its done this a few time but ussually I csn get it to start by holding it wide open. Now it just wont start at all.
Last edited by 89blaster89; May 13, 2014 at 08:42 AM.
#4
As usual, start here: http://personal.utulsa.edu/~nathan-b...28fuelpump.pdf
Fuel pump relay? There is the EFI relay (which has nothing to do with your problem; that relay powers the B+ and you've confirmed that works) and the Circuit Opening Relay.
When you turn the key to STA that (alone) should cause the COR to close. With the key in ON, pushing the VAF flap should cause the COR to close. So unless you've mis-described this last test, you've got a wiring problem in the key switch.
But, it is much more likely a dead COR, as bypassing it (with the jumper) makes the pump run, and closing the COR (either with the VAF or the key switch) does not. So pull it out and run the tests. http://personal.utulsa.edu/~nathan-b...38circuito.pdf
Don't have a multimeter? Well, you could just replace the COR "on the blind" for about $85 http://www.toyotapartsoverstock.com/...ssembly=496770 Or you could get a meter. http://www.harborfreight.com/7-funct...ter-98025.html for about $5.50
Fuel pump relay? There is the EFI relay (which has nothing to do with your problem; that relay powers the B+ and you've confirmed that works) and the Circuit Opening Relay.
When you turn the key to STA that (alone) should cause the COR to close. With the key in ON, pushing the VAF flap should cause the COR to close. So unless you've mis-described this last test, you've got a wiring problem in the key switch.
But, it is much more likely a dead COR, as bypassing it (with the jumper) makes the pump run, and closing the COR (either with the VAF or the key switch) does not. So pull it out and run the tests. http://personal.utulsa.edu/~nathan-b...38circuito.pdf
Don't have a multimeter? Well, you could just replace the COR "on the blind" for about $85 http://www.toyotapartsoverstock.com/...ssembly=496770 Or you could get a meter. http://www.harborfreight.com/7-funct...ter-98025.html for about $5.50
#6
And you know the COR is good because ...? Of course, if the other truck is bone stock and was working when you pulled the COR, it probably was good. But since you've eliminated almost everything BUT the COR, you'll want to run the tests on it.
If the COR is working, there's only a few inches of wire left to test. I'd start by confirming that there is 12v on the B+ pin of the relay socket (you know there is 12v on the B+ pin of the diagnostic connector), and that there is continuity from the FP pin of the socket to the diagnostic connector (because you know there is continuity from the diagnostic connector to the pump.)
If the COR is working, there's only a few inches of wire left to test. I'd start by confirming that there is 12v on the B+ pin of the relay socket (you know there is 12v on the B+ pin of the diagnostic connector), and that there is continuity from the FP pin of the socket to the diagnostic connector (because you know there is continuity from the diagnostic connector to the pump.)
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#8
Ok well I just went out and cranked it over for about 10 seconds and it started. But still what the heck is causing this?
#9
Loose wire, loose relay socket, loose ignition switch, loose VAF connector, displaced magnet in VAF, burned-out winding in fuel pump stator, .....
Without using a multimeter to track where the circuit is opening, you are farther from the solution than you will ever be.
Without using a multimeter to track where the circuit is opening, you are farther from the solution than you will ever be.
#10
I can use a multimeter at school tommorow. What do I need to check exactly?
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