Fuel pump issues

[lyttlea]

Hi guys,

I'm a little unlucky at the moment with my challenger 2000, one thing fixed only for another to keep me on dry land!

Out last weekend and suddenly lost power, luckily just off the dock, the problem is the fuel pump is not working. No clicking when I turn the key.

Here is what I have done:

1) pump really test from a 12v battery and the switch is working a ok
2) 3 amp fuse is good
3) 12 volts check on both terminals of the pump on the VST
4) jump the negative terminal on the VST to ground and both the lift pump and high pressure pump turn on
5) put a new ECU on

Double checked all the connections for continuity and can't find a thing wrong.

Any suggestions guys?

Thanks

Alan

 

[Sportster-2001-951C-Stock]

Perhaps your ECM isn't receiving the key on signal? (Looks like pin 7 purple wire.) Does the horn sound as described?

"1/2 second after ignition key is turned to “ON”, and power is applied to ECM, warning lamps will illuminate for 1/2 second and horn will beep for 1/2 second."

The ECM turns on the fuel pump by bringing the Red wire with purple stripe pin 2 of ECM to low voltage, this creates a 12v drop across the fuel pump.

Also, I believe the ECM on this model will turn on the fuel pump for 30 seconds with key on engine off..

 

[Dr Honda]

OK... lets start with... What engine do you have? I'm assuming a 240, but even if it is... what version is it? Let us know, and add it to your signature or info so it's always posted.


Just a quick FYI...


The lift pump only pumps while you are cranking. Some ECU's will pulse it when the key is on for a few second. But generally... while running... it's off. (The flat, mechanical pulse pump supplies fuel while running) And honestly... if there is fuel in the vapor tank... it's not even needed.

As far as the high pressure pump... if you manually ground it (forcing it on) will the engine start?