new to forum bimmerphile since '92

[e30Slave]

Hi, thanks in advance for any relevant info on this no start problem that just gets more and more mysterious. had a fuel pump go(possibly something else as well) Now have a used but working(as best I can tell) pump. My car has only one in tank pump. Car turns over strongly but no start. Spark tests good, just cannot get the fuel pump to run unless I connect it directly to the battery. With the relay or a jumper in place I blow a fuse every time. Have established continuity between relay socket that goes to pump and connector and resistance test read zero resistance. Have good ground at connector. Pretty much ruled out ignition switch, ruled out errant code issue from OBC. Main relay seems fine. Can't test fp current draw because of blowing fuses.. Idle air stabilizer valve seems OK, as well as injectors. In the bentley manual electrical tests for the fuel system(at the motronic connector) everything checks out except the full throttle switch (related? or an adjustment thing) and the "FP relay control" (test blows the fp fuse as well) Air flow sensor and potentiometer seem fine. Have I missed something? Unfortunately real low on money so I'm limited in what else I can replace to solve this (for now). Has anyone had this problem? I'm stumped- and this is weekend three without the whip..

[Speedy-325is]

is the fuel pump for ur exact car, what brand is it? where did u get it? it sounds like a short. did u wire it up correctly?

welcome to the forums!

Mark

[Speedy-325is]

what yr/model is ur ride?

[e30Slave]

it's an '89 325is w/ some typical mods. The fuel pump came from a junkyard so even though I have heard it run I cannot say for sure what condition it's in. Seems like a short somewhere but the bentley manual-as exhaustive as it is- doesn't get specific enough with the late e30 models for me to figure out where a lot of the wiring goes. Thanks for the reply!

[97alpineM3]

If you could... and I dont exactly know if you could or not... I'd back trace every wire from your fuel pump to the battery... and make sure there is no shorts... or exposed wire touching any where... that would cause it to blow fues all day long..

And are you sure your using the right Fuel pump... if you have a different one.. it might take more or less power draw from the power source.. which would also blow fues all day.

I'd make sure that all the connects on the newer fuel pump are clean... dirty connections can have a major roll in having a short.. and not exactly getting the right amount of power to a component.

GOOD LUCK!!!!

[BMWJNKY]

I don't know what year fuel pump you have but it makes a difference. In November of '87 there was a change. The part # for the pump you should be using is 16 14 1 179 992.