fuel pump not working

[natenate]

Hi
I took my fuel pump off to check it. Its on a 230sl but its the later model the shorter one. Checked pumo all was OK. Bench tested it straight to battery and it is working fine. Connected to the car and mounted it and nothing! Could it be the relay? Or something else? Was working fine when I took it off. Where should I start?? Regret taking it off to check it big time

[ejboyd5]

Perhaps the fuse blew during removal or reinstallation of the fuel pump?

[natenate]

Checked it and it had blown. Changed it and still nothing. Will out a tester on it tomorrow and if I'm getting any thing from the relay. I know the relay is pricey so I'm hoping its not that. Anything I could be missing?

[ctaylor738]

There's no relay unless someone installed one.  Current flow is ignition switch to F4 to pump.  You might have a bad wire on the positive or the ground side.

[ja17]

Yes, as Chuck indicated, no relay. Could be a defective fuel pump which drawing too much current for the fuse. Check wires to make sure you have good ground and 12 volts. You can also try disconnecting the wires from the car and hook up an external power source like a battery jump pack. If everything works with the external power, then the problem must be a wiring related issue. Or an excessive current draw issue from the fuel pump.

[natenate]

Thanks for the help. Was a problem at the terminal.