Cranks but no start?

[jamiholzbach]

The car cranks, but won't start. The fuel pump won't run, and I've got no spark. The voltage at the fuel pump relay reads 12V until I crank the motor, then it drops down to 2-3V. the battery reads 12V but at the other end of the small cable(w/ fusable link) I read 12V until I crank or put the ingnition to run, then it drops down to 2-3V at the block on the firewall. If I wait till the next day, it does it again(starts at 12v then drops down to 2-3v and stays that way as long as I'm trying to test it). WTF!

[jamiholzbach]

corrosion?

anybody see anything like this before?

[OSM e30]

check your crank position sensor, exact same thing happened to me

[jamiholzbach]

It was corrosion!!!

the fusable link was corroded! I started checking voltage through the cable jacket, and when I got to the link, I had 12v on one side, moved 1/8" over, and nothing. I couldn't even read continuity through it, so...
Now what do I replace it with?

[jlevie]

You could bypass the fusible link, or replace it with a fuse. My preference would be a fuse and I think I'd try a 30a to start with.

[StereoInstaller1]

I am using an AGU type car stereo fuseholder, available at most all car stereo shops for about $10 and a 50A fuse.

[houstonh]

Where is the fusable link located on a 89 325i coupe?
Is this in the trunk? or engine bay?

Is it the "flat spot" on the wire? just curious.. I think this could be my problem.

[jlevie]

Is it the "flat spot" on the wire?

Yep.

[jamiholzbach]

$.50 fix

I spent $50 to get the car towed home:(, and $.50 to fix it with six inches of fusible link wire.:D

[ethirdy]

Where is the fusable link located on a 89 325i coupe?
Is this in the trunk? or engine bay?

Is it the "flat spot" on the wire? just curious.. I think this could be my problem.

Where is it on an 86 325e? Would jumpstarting the opposite terminals of the batteries blow this? (non Bmw owners should never be trusted with jumper cables LOL)