Issue starting my 2006 330i.
When I hit the ignition button, engine is slow to turn over, but ultimately starts. Happening more often (coinciding with weather getting colder) and the pace of turning over is getting slower. This morning, it just barely started from cold start. I let it run 10 minutes or so. Then shut it off and started again. It fired right up without the slow turning over issue.
Does this sound like a battery, alternator, or possibly an ignition issue?
Check the battery voltage first. What is it? How old? I'd have the fuel pressure checked next if all is good.
Run a tank of high powered fuel injector cleaner through it and have the battery tested. If that doesn't do it, you may have a lose ground or an electrical component somewhere that is slowly draining the battery.
I don't understand how the fuel pressure or fuel injectors would impact the car turning over slowly. Can you elaborate?
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