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Discussion Starter #1
Trying to diagnose a lack of fuel pressure in my '82; when cranking, only .15 volts go to the fuel pump. Also, the fuel level gauge doesn't do anything, just hangs below zero. This is a car that was parked for a year after being driven in the Wisconsin winter (AAAARGGGHHH!). Anyone have any suggestions?
 

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Discussion Starter #2
When fuel pump is jumpered, it spins and works. Something in between is defying us.
 

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Does this car have a Circuit Opening Relay? Also check out the fuel pump relay/fuses first.
 

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When fuel pump is jumpered, it spins and works. Something in between is defying us.
It wouldn't be in between.
Take off the airfilter and reach up inside and prop open the flapper door (a screwdriver should work). Turn on the key and check for the fuelpump running - you don't need to crank it over. Just a diagnostic check let us know if you have your 12v to the fp when the flapper door is open and the key on. We can go from there
 

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Discussion Starter #6
It wouldn't be in between.
Take off the airfilter and reach up inside and prop open the flapper door (a screwdriver should work). Turn on the key and check for the fuelpump running - you don't need to crank it over. Just a diagnostic check let us know if you have your 12v to the fp when the flapper door is open and the key on. We can go from there
Fuel pump DOES RUN when flapper door is opened. Where next?
 

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Discussion Starter #7
Also, I should add, I am getting spark off the coil, and the firing order is correct. This car was parked in running condition, sat for most of a year, and the PO supposedly wasn't getting any fuel pressure when he tried to start it. I'm going to pull the plugs later and see what they look like. FWIW, after trying to start it a few times, opening the flapper door does not seem to kick on the fuel pump - I am assuming that's because the system is pressurized now.

Judging from the PO's shitty gauge wiring, mismatched spark plug wires, and other crap, there's a decent chance he 'fixed' something that was never broken.
 

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The system does not know pressurized or not. AFM flap open, key on, it should get 12v.

Do exactly this.

1: Unplug fuel pump power plug at the tank access under the rear cargo hatch. Get your multimeter out, we are checking the two pins coming from the car, not the ones going to the pump.

2: Insert jumper or hold the AFM open, check voltage between the two pins (tell me what you get). Now check voltage between each pin and body ground (tell me what you get). Now check resistance between the one that doesn't return positive voltage in the previous two checks (tell me what you get).

--billyM
 

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Discussion Starter #9
Well, we've figured out the problem. First of all, my EFI fuse was blown - fuel pump operates normally again. Goes to show that you overlook dumb stuff when you haven't had a break in a while.

An MSD 6AL was (very poorly) installed on my car. We undid that whole thing, and have determined that it also has a MSD Blaster coil. The ignitor isn't hooked up to anything, and the wire routing isn't explained in the Toyota '82 wiring diagram; there are pink, white, brown, black and yellow wires. There's an eyelet on the brown wire, and the black one was cut off for some reason. Anyone know how to run these?
 

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Brown goes to the + side of coil and Black is - to coil from ignitor.
Pink and white go to dizzy
Brown from coil is + power Not sure about the yellow.(Tach maybe)
 

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Hope the Holidays are treating you well...could a bad fuel-pump be responsible for blowing the 15amp EFI fuse consistantly? Blk '83 wont start, replaced the EFI, and main relays in the fuse box, as well as the other main relay attached to the fender well, and it still blows the fuse....grounds check out, but could use replacing with better gauge wires, should I jack her up, and go after the fuel pump??? Can you get to the fuel-pump thru the tire-well?
If a fuel pump is recomended...do you have any suggestions?
 

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In the hatch om the right side is a cover with 3 screws. Remove the cover and unplug the two wire plug that does not go in to the tank in that area. Test the volts on the harness side (body harness) with the fuel pump jumper and key on. Then test the pump for a short by testing the Ohms.
 
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