Ignition problems in a 735i

[Hoofbeats]

My 1988 735i has taken a fancy to refusing to start. Sometimes she'll start in the morning, but if I stop for gas, food, etc., she won't start again to get me home. Sometimes she won't start at all. Sometimes she'll have to sit a half hour or more before she'll start to purr. Any ideas? Oh yes, sometimes all the lights go out too!
Emily

 

[cbe317]

First thing I would do is have all the connections and cabling from the Battery Inspected. Then I would check the fuse block to make sure there is no moisture inside. I have seen a little water completely destroy a BMW fuse block. I had a VW cabriolet that would do the exact same thing. That ended up being a bad starter. When the starter would get hot it would not turn. Let it cool a few mins. and presto! started right up.
Hope this helps. C.

 

[Hoofbeats]

Thanks, we'll check those out. The guy who's worked on it thinks it's in the fuel pump, but once it starts it runs like a Swiss watch. I'm more inclined to think it's in the starting mechanism or a relay that heats up ... I like the battery cable idea too.