89 325i sat 4 years turns over. spark. no run - BMW Forum

illuminoti · 12-25-2008, 11:37 PM

hello. my 89 325i sat for about 4 years. jumped it and moved it twice. this time i was moving and very distracted. i connected the poles on my 325 battery backward. i didnt try to start it or turn the key at all. after i connected it right i tried to jump it, it turns over, i have spark, will run with starter fluid. didnt seem to be getting fuel. checked the fuel pump fuse. i have power to the fuel pump relay. i dont have power @ the fuel pump. i do if i jump the fuel pump relay connections. with the relay in i hav power to the relay but not on any of the other pins on the relay (with and without the key on). i dont hear the fuel pump doing anything even when i jump the relay. could i have killed the ecu by hooking up the battery backwards and the fuel pump have gummed up from sitting so long? or maybe could i have fried both? also with the fuel pump relay in and the key on i get a clicking sound almost like a short on the connection going to the ecu when i use my voltage light but no voltage. i should hav voltage there right? i swapped relays but could both be bad? if anyone has any ideas i would greatly appreciate it. i just ordered a fuel pump and 2 relays. maybe my ecu? thank you everyone in advance.

witeshark · 12-25-2008, 11:41 PM

Each of the possible electric issues you listed needs to be checked one at a time. Sorry, there are no short cuts for this...

illuminoti · 12-26-2008, 09:53 AM

i have checked them one at a time. i was just listing what all ive come up with. i will replace everything involved i guess. i ordered the fuel pump and relays and realized it could be the ecu. any reason for the clicking but no voltage on the relay lead going to the ecu? is that normal? shouldnt i have voltage on that lead with the key on? or just when the car is turning over? thanks witeshark and everyone.

witeshark · 12-26-2008, 10:55 AM

The relay to the ECU may be bad.

illuminoti · 12-26-2008, 11:18 AM

thanks! do you know if that would be relay 1 or relay 2 in my haynes manual? i know relay 1 goes to the fuel pump. both have leads that go to the ecu. ive swapped the relays with the same result. i appreciate your help.

witeshark · 12-26-2008, 11:41 AM

You may wanna check the voltage regulator.

silversled · 12-28-2008, 07:14 PM

why not go directly from the battery to fuel pump itself?....screw the relay...good luck

illuminoti · 12-29-2008, 12:34 PM

yep, went from battery directly to the fuel pump. seemed like it tried to run but sounded almost like it was seized up or something. as soon as i recieve the pump ill replace it but still doesnt make sense why i wouldnt have voltage at the fuel pump with the relay in. when i jump the relay i do have voltage. i thought i was suppose to have voltage at the pump with the key on. or am i suppose to turn the engine over to see voltage at the pump? someone told me the pump should run with the key on. then i read that it doesnt prime the system when the key is on only pumps fuel when you turn the engine over. i have to go down to the garage where the car is to check voltage when i turn the car over. thanks again for everyones help

marti5 · 12-29-2008, 12:36 PM

The pump will only start pumping when you crank the engine and not with just the key turned on.