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For the past few weeks my 528i has occasionally not started on the first try. Usually a cold start. Then always goes on the second. Well, that is until this AM. Nothing at all. Where should I start looking for the cause?

Engine turns over easily but did not catch. Main Fuel pump is less than a year old. I checked the fuel pump fuse and there's no visible corrosion. It's also a new ceramic fuse. Replaced combination relay late last year.

I seem to have also misplaced my Haynes manual as well. Do any of you know the specs to test my ignition coil and cold start valve resistances off hand?

It should start fine without the cold start valve, especially this time of year. So cross that off. Test the fuel pump by pulling off the intake boot and pushing in on the AFM flap with the ignition on. That should turn on the fuel pump. Test ignition by removing the cap and pulling off the high voltage lead from the coil. Then test for spark by holding or wedging it close, but not on something metal that's grounded and rock the dist rotor back and forth. There's usually enough play from the centrifugal advance to allow the field to make and break.

Thanks. I got it started when I got home from work yesterday. Started like nothing happened. Then this morning it decided to not start again. This time I did smell fuel and I checked the fuel pump and it's working. Looking like ignition. Not getting spark.

I would test spark next time it doesn't start. Take an old spark plug and put it in either the coil lead or a spark plug wire end. Rest the side of the spark plug on the valve cover so it gets a ground. DO NOT HOLD THE PLUG!!! spin the engine over and check to see if there is a spark and what color the spark is. Blue to white is good. Orange to red is bad... No spark tells you its the coil or further up the line. There may be corrosion in the coil leads that when it warms up makes proper contact.

Good luck.
Sam

It also doesn't hurt to give the Ignition module a good whack. Those are known failure items (I don't want to say common, but known to fail).

A good thing to do is freshen the contacts of the connector at the bottom of the ICU.
A bad design encouraging moisture/condensation/water to collect inviting electrical failure.