Hello everyone,

I did some searching on this first but could not find anything that may help.

1990 E34 525i M20

I changed my oil and filter two days back, had to disconnect battery to get to the oil filter and reconnected everything once I was done. When I tried to start it this morning, I got a clicking sound and tried again. It started but it died after two or so seconds because I didn't give it a little gas (i usually have to). When I turned the key again I just get a click sound and nothing happens. The engine would at first barely turn and then finally dies to nothing. The dashboard lights up and the normal warning sounds go off but the engine wont turn. Every time I turn the key to ignition I hear a click. I figured it was a dead battery because my E28 made the same clicking sound when there was insufficient power.

I got home and started working on the car again this evening, charged the battery first. I left the battery charger on the battery in Start mode and I tried to turn the engine again but same problem. The dashboard and everything lights up but the engine never turns.

If i leave the key in the ignition stage, the dashboard is a little erratic. I can see the check engine light slightly flickering, and every few seconds the speedometer gauge jumps and falls flat again.

I also noticed that under the hood, on the passenger side I have a cable that runs from by the firewall towards the battery (not directly) but the end is loose. It has a plastic black box attached mid way and a female type of end you would attach by a screw or bolt. I'm not sure where this part goes, and i don't remember if it was ever connected to anything. I do remember accidentally pulling it when changing the battery but I don't think I could have ripped it out of anywhere, the =-O end is undamaged. I'll try and get a picture up as soon as i can.

This should be a simple fix, I only changed the oil for crying out loud!

Thanks for your time!