Fuel Pump Electrical problem

[M4DE30]

My fuel pump shit on me so Ive gotten another replacement one. I tested the replacement to make sure it would turn on and it worked. I plug it in assuming it would work but it didn't. I thought it was some kind of contact with the fuel pump and the connector so I spliced in a new fuel pump connector. It still doesnt work; I've already tried a new fuse also, still nothing. I've tried relays, still nothing . I really don't know what the problem is and hope you R3v's can help me out. Could it be the something with the DME? or something cause I'm x100000.
Thanks

-B

[jlevie]

First of all you need to know that the fuel pump is controlled by the DME and will only run when the DME sees timing data from a rotating engine. If there is spark when cranking the engine, the DME is running and has timing data. If the fuel pump isn't running then, look to the fuel pump relay, fuse, adn wiring. If there is no spark when cranking the engine the fuel pump won't be running either and you should look to the main relay, CPS, DME, fusible link, etc.

[M4DE30]

I checked everything besides the DME. Might be so. Thanks

[matt0300]

Did u check all ur relays? Ur cps? Did u ground pin 30 to see if ur fuel pump was still good? Check k5 relay (I think).

[M4DE30]

I checked all the relays/fuses. Fuel pump is still good, I tested it. I beginning to think its the CPS. I remembered I started it and heard a weird squeak sound so I shut it off. I tried to start again and it failed. But funny thing is, the fuel pump went out too if it is the CPS. Gonna check CPS in a bit. Anyone know where the fusible link is?

[M4DE30]

Put in a new DME and still nothing. Swapped newer relays in still nothing. IDK what the fuck it is. Could it really be the CPS?

[jlevie]

Is there spark when cranking the engine? No spark could mean a failed CPS, which in turn would mean no fuel pump operation.

[M4DE30]

Theres crank thats why i decided not to look at it. Its weird because I swapped the main relay i was running during the fuel pump failure with my buddys and his e30 wont crank but then when he puts his relay in my car it still wont start? I'm thinking maybe something shorted. But have no clue where it can be.

[nando]

just because it's turning over doesn't mean there's an RPM signal to the ECU. you need to check for spark.

[matt0300]

Did u switch up the cps and the lead coming from the sixth spark plug?

[M4DE30]

I checked if there was any spark. No spark. Tried other wires. No spark. Gonna purchase all new relays and a CPS. Hopefully this is the problem and doesnt lead to anything else. Thanks for the help guys; Ill keep you guys updated.



-B

[M4DE30]

So the CPS was dirty as fuck. And two relays were out. Swapped em out and got the dirty 30 up and running. Thanks for the help guys.

-B