Starting Problem 325e

Hello everyone

I am having a starting problem which does not showup in any of the troubleshooting sections of the service manuals I have and was wondering if anyone could help.

This problem started as the weather grew cooler. When the engine is cold it will crank and crank but not fire over, other times it starts just fine. If I turn the ignition switch off after a few seconds and try again on the 3rd or 4th try it tries to fire but will not catch. If I continue to crank it only runs down the battery. If it doesn't fire after a few attempts I role start it and it fires right over. Sometimes it runs just fine and after a short warm up can be driven with no problem. Other times it will just stop running. If it ran for a few minutes it can be key started but if it only ran for a few seconds it requires a roll start.
Of course it is very intermittent some days it's just fine other days it will just stop even when moving at highway speed. It just starts slowing down. Often it will restart without me having done anything, other times it will roll untill it stops. But it restarts just fine. Some times it will do it all day other times it only does it till it warms up and then starts just fine even if left sitting for a few hours or so. I have tried the following things.
New spark plugs, new fuel filter, new air cleaner. Checked for vacume leaks. Checked fuel pumps. checked cold start valvue and injectors and everything seems fine.

Can anyone offer any other ideas as to what it might be.

Thanks

John

Did you check these things when the weather was nice or cold? I guess the next step would be to take it to a mechanic.