I had posted for help with my 96 SL1 and we have hit anothe hurtle. Changed out the fuel pump because the old one was bad and now the new one we JUST put in today is not wanting to work. We took out the dash relay and it was hot. What could be making the fuel pump short? I am just about tired of this car. Any help PLEASE

 

The fuel pump relay is in the underhood fuse box and labeled for identification. The test for the fuel pump would be to remove the relay, identify the socket pins 30 and 87, wire a jumper between them to send 12v directly to the fuel pump through the wiring harness. Now that you know where the wiring is located from dropping the fuel tank you can try this test. I'm not sure if the ignition key must be on but you can try this with or without the ignition on. If the pump doesn't run you'll have to trace the 12v going to the fuel pump, perhaps from the tank side wiring. Locate the wiring harness to the fuel pump and with the pump relay socket jumpered you can probe for the 12v that should be on at least one wire to the pump. The other wire is for the ground to complete the pump circuit. Be sure there's a ground connection and that it isn't corroded. Look/examine the connector pins/sockets for corrosion too.


I'm not sure what the dash relay is for but it shouldn't be for the fuel pump. If the relay is wired into the harness it may be from an aftermarket alarm system? Remote keyless system? Is there a fuse for this relay inline near this relay? It may be a fuel pump or starter interrupt and in any case it shouldn't be hot and may indicate something else is wrong that is interfering with the fuel pump operation. If possible, find the wiring to this dash relay and bypass it then try to start the engine again.


Another way to check for spark and fuel are to remove the coil wires and have someone crank the engine while you look at the coils arc. Arcing indicates that the ignition system is working. The fuel pump test involves just turning the key to the ON/RUN position and listening for the quiet hum/hiss of the fuel pump priming for 2-3 seconds then shuts down. Repeat this several times if necessary to listen for this hum/hiss. Then locate the fuel rail where a test valve (schrader valve)is capped, over the engine area. Remove the cap, cover with a rag and depress the valve stem (its the same as the tire valve) where a healthy spray offuel should shoot out. The spray test is to verify the fuel pump/pressure is available to the injectors.