86 325es won't start

[SEdgell]

I have an 86 es, it is getting fuel, but no spark. I can ground the coil and release it and get a spark then, so the coil is good. I've checked the crank position sensors, the resistence is low (550 ohms) on both, but they are putting out the right signal according to the bentley manual. So I haven't quite ruled them out yet, but I'm lost. It has new plugs, wires look fine, distributor looks good, new fuel pressure regulator. The ignition switch was busted, but it and the lock cylinder have been replaced with new BMW parts. I have two ecus and I've tried both, but it doesn't act any different with either computer. I would like to see what would happen if I replaced the speed and reference sensor, but I don't want to spend the money if that wouldn't fix the problem. Any suggestions? I'm not sure what else to check.

[jlevie]

Have you checked to see if power is reaching the DME? If so, a no spark condition when cranking is most likely to be caused by a lack of timing reference data to the DME.

[SchnellerVert]

Condition of battery?

[e30_lover_CT]

speed and reference sensor are likely culprits... replace both if you do one, since they're a PITA to reach. I just had the reference sensor go on my car, gave me similar problems that you're describing. Come to think of it, the same thing happened on my 85 325e a few years back. Seems to be a likely problem for a 22-year old car..

[redhatpat]

Check the condition of your rotor, cap and spark plug wires. The spark plug wires are expensive on e30s, and as a result they usually don't get changed out until after they fail. Ask me now I know that. ;)

[SEdgell]

Where is the DME located? The power supply is the fusable link coming off the battery in the trunk right? If that is fine, I may go ahead and get the speed and reference sensors and hope that does it, if not then that will be $90 wasted. Any other suggestions on what to check would be great.

[e30_lover_CT]

I may go ahead and get the speed and reference sensors and hope that does it, if not then that will be $90 wasted.

It's never wasted money to install new components on a car that's 22 years old...especially ones that are notorious for failing and leaving you stranded. It's preventative maintenance. I plan on replacing everything electrical on my engine that I can afford to without going into the poor house...I don't want to take the chance of having my only car leave me stranded because I wanted to save a buck...:???:

[kenika65]

Had the same problem on my 86es and it was the fusabul link in the trunk about 6in from the batter on the small power wire... it was blown, put a fuse in there fired right up... but now its upgraded to 1.3 Motronic!

[SEdgell]

My fusable link has been replaced with a fuse block. I have power going into and coming out of it, but I went and got a universal fusable link and I'm going to put it on shortly and see what happens. I called my local BMW dealer and they couldn't even find a fusable link listed for my es. So hopefully this will work, but if it doesn't then I'm going to replace the speed and reference sensors....wish me luck