1984 318i Is causing my hair to fall out!

[RagtopE30]

Hi everyone. I have a friend who drives a 1984 318i and it drove well for the first two years he had it, he has had it for 4 years now. What happened was this, one day he was driving along and the car just died, no sputtering no lurching, just died. You could crank it all you want but no dice. Once the car sat over night it would start up fine. This continued at random itervals for a period of 3 or 4 weeks. Then it became more methodical. He could start the car when it was cold and drive it for approx 10 mins and it would die. Since he was new to bmw's and had just paid to get it painted and swap out the interior, he proceeded to throw more money at it with no results. I came back into the picture after a year and at this point he had replaced the following items:
Distibutor
Thermo-time-switch
Thermostat
Waterpump
both fuel pumps
coil
spark plugs
wires
distributor cap and rotor
fuel filter
O2 sensor
And all these items were brand spanking new.

After all this money he couldnt get it running. I got there and reran the plug wires and set the timing. The car is still showing the same symtoms except now it doesnt seem to be based purely on the 10mins run time. The last time she ran, she ran for about 30mins including a test drive. Purred like a kitten, then as we were celebrating thinking we had done it with our latest tinkering, she died. I cranked the engine over to no avail. I then, out of pure frustration (Yes I know the car is injected and this move does nothing for it) I pumped the accelerator pedal while cranking the engine and it started then died. I did this several more times and no matter what I did I couldnt get it to stay running. When I say started and died I mean it was that quick! Like some one shot a little starter fluid in the intake.

SO please help me out here!!! I dont know where else to look. I do have a Bently but havent been able to come to a solution using it. And yes I know my way around a shop, I have been turning wrenches professionally for 16years.
Any input would be appreciated!
Thanks
Matt

[JakeP]

Try pulling off the fuel return line and see if you're getting fuel to the rail. If you have fuel, do a flow test. Also just for giggles, check the ground strap from your engine to the body.

[gnarlycreature]

Crank Position Sensor.

[mr.vang]

maybe a bad AFM.

[StereoInstaller1]

Crank Position Sensor.

Does not have one.

Your best bet is to bypass your main relay temporarily...the symptoms you are describing sound exactly like a main relay issue.

[Good & Tight]

Sounds like a bad connection, while it's running move around the connections at the fire wall.

[RagtopE30]

The AFM has been swapped with another known working AFM from another 318i and the issue persists.

It is possible that there is a connection issue but the shut down occurs even if you let the car idle for a while.

The main relay on this car is a beast, but I will consult my Bently for the bypass procedure or at least the wiring diagram for the relay. Any hints on the bypassing would be appreciated

[blunttech]

my e28 does this same thing. frustrating to say the least. I thought I had it after super duper reflowed some solder joints in the ecu but it just died again yesterday. mine will run for a week or more and then strand you when you have to be somewhere.

[Stevie30]

Crank Position Sensor.

Check the wire to the crank position sensor. It will sometime come loose from the clips on the timing cover, rub the fan pulley where the insulation and shield will be cut, and short against the pulley. One like this drove me crazy for about six months. It would start OK when cold; You never knew when it got warmed up if it would start or leave you stranded.

[1fastm50]

Check your ground straps and if in doubt grab jumper cables. Hook one on the Body and the other on the engine. Like a big ground strap.

[JakeP]

no response to my fuel suggestion? :( it's something free and easy to try.

[StereoInstaller1]

Check the wire to the crank position sensor.

IT IS AN M10, IT DOES NOT HAVE A CRANK POSITION SENSOR!

Hope that gets it across.

Here is how to bypass your main relay: make a jumper wire using 3 male 1/4" spade lugs and a foot or so of wire. Jumper the large red wire to the other large red wire AND the red/white wire (remove the relay block to see properly) adn start your car.

YOU WILL NOT BE ABLE TO SHUT THE CAR OFF WITH THE JUMPER IN PLACE.

So, go drive it, see what happens, then get a main relay from Blunttech.com

GL!

BTW: if you don't have your electrical manual, go to www.wedophones.com and click the link to manuals, then look for automotive, then BMW, then download your manual.

Luke

[RagtopE30]

Thanks for the help^^! This wouldnt be so freakin hard if it were a 2.5i I know how to troubleshoot/bypass every relay in that system. Its just the 318i has that funky main relay.