Author Topic: think my temper isnt the only thing thats a short!! fuel pump woes inside. help! (Read 5010 times)

mike30 · « **on:** July 24, 2007, 04:58:59 PM »

edit: added some cliffs

done some research but still have questions. to start off my car is a 91 m50 swapped 318is. no i didnt do the swap myself. yes, i bought it post swap. (in school and wouldnt ever have the time/money to swap it myself until i'm done with school)

anyway, i've had the car two months or so. got home from work last week, parked it outside for bout an hour. got in to go to the gym and she started, as i was rolling my windows down i got a rough idle. i shut the music off to listen and boom, stalled. started again, idled less times, still rough, then stalled. started again, less cranks, stalled. and again, less cranks, then stall.

great.

first instinct said fuel. the infamous jordan said jump pins 30 and 86 on relay k3, so i did, and voila, heard the pump and car started. car wouldnt shut off tho, so i stalled it in gear. started fine, stalled it in gear to shut it off and remove the wire to see if it'd work without the wire. it did, but within minutes it stalled and was back to its old ways.

fast foward to yesterday. finally found my haynes manual (yea big help! :rolleyes: haha) and jumped pins 30 and 87 like it says in there, still no luck. my old man was touching stuff here and there, nothing in particular, and it finally started working again. 10 min later i drove it down to parts store to take it for a spin and pick up a hose clamp (found some air/vacuum leaks too

) got in the car to go home and no start again.

fuses are all good. fuel filter was replaced first day i had this problem last week.

sorry for the long post.

cliffs: car cranks but doesnt start. jumping relay worked once, doesnt work anymore. dont hear any fuel pump buzzing or whirring noise. what should i check with a voltmeter (now that i have one to use) and whats the difference between the MAIN relay and the FUEL PUMP relay and where are they located?

thanks so much. this is my daily!!! arggg

-mike

D. Clay · « **Reply #1 on:** July 24, 2007, 07:13:25 PM »

Wiggle the plug that goes on the fuel pump.

mike30 · « **Reply #2 on:** July 24, 2007, 07:18:07 PM »

Quote from: D. Clay;30310

Wiggle the plug that goes on the fuel pump.

ha, yea i saw your one reply on an old fuel pump thread. will try that again tho.

anyone have a pic or schematic of the relays. would really help to know FOR SURE which relay is the main and which of them is the fuel pump.

thanks

mike30 · « **Reply #3 on:** July 24, 2007, 10:19:45 PM »

just an update. lead going to the 2 prong connector at the fuel pump gets about 10.5 volts when the car is cranking. should this be enough to get the pump going?

b318isp · « **Reply #4 on:** July 25, 2007, 08:49:53 AM »

Quote from: mike30;30332

just an update. lead going to the 2 prong connector at the fuel pump gets about 10.5 volts when the car is cranking. should this be enough to get the pump going?

Yes, but it sounds like the pump may have gone west.

mike30 · « **Reply #5 on:** July 25, 2007, 03:41:10 PM »

Quote from: b318isp;30357

Yes, but it sounds like the pump may have gone west.

yup think so. i need to find one that is able to come back east

think used fuel pump is a bad idea?

and how do i know if its the main pump and not the transfer pump (or whatever other second part it is our cars have?)

Shocker · « **Reply #6 on:** July 25, 2007, 06:54:27 PM »

E30 M42 only has 1 fuel pump in the tank. Also I would just buy a new one, because a used one might fail in couple hundred miles and you'll be in the same boat again. E30 325's have two pumps.