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celicaman97
03-30-2013, 12:33 AM
Hello, my fuel pump is not working and i noticed my fuel pump relay in the box by the a/c compressor is missing, is it needed ?? also how bad is the fuel pump replacement?

Hookecho
03-30-2013, 12:43 AM
Only the Alltrac/GT4 had the relay. Fuel pump replacement is really easy. It's under the back seat. Just remember you're fooling around with gas and be careful.

celicaman97
03-30-2013, 01:06 AM
ok what else can i check before i replace the fuel pump? i check the EFI fuse, it is good

Hookecho
03-30-2013, 11:32 PM
What is the problem with the motor? If you know for sure the motor is not getting fuel then first jump FP and B+ in the diagnostic terminal and listen for the pump to run with the ignition on. If you hear it running check the fuel pressure per the BGB. If pressure is good then start using a DMM to check voltage at the ECU. Somehow the ECU may not be getting the signal that the engine is cranking or there could be a short in one of several wires that affect fueling. The BGB has good flow charts for this procedure but I would be glad to walk you through it. A DMM will save you time and money.

93celicaconv
03-31-2013, 11:32 PM
The ECU doesn't turn the fuel pump on when the engine cranks - but it does once the engine starts!

When the engine cranks, the key in the START position turns the fuel pump on. Once the engine starts, the ECU latches in and keeps the fuel pump running. There is a COR (circuit opening relay) used for the fuel pump, it is located on a bracket off the the ECU. When you jumper FP & B+ on the diagnostic terminal, you bypass this COR to turn the fuel pump on with the key in the ON position. That is why the test with FP & B+ is important, to know if you have a fuel pump issue or a COR issue.