View Full Version : Starting problem in minus temperatures

01-25-2013, 08:24 PM
Have a 2002 325i, it has difficulty starting first thing in the morning, I used to repeatedly crank until it started until I discovered that I can tell when it will start just by turning the ignition on and wait for a buzz noise which I assume is the fuel pump(?) once it does start it drives fine and starts no problem throughout the day up until the next morning.
It was minus 20 the other morning and there was no way it would start, eventually 5 hrs later it started and I took it into a local shop, they replaced the boots on the mass air flow sensor which were cracked and split on the underside, the next morning it didn't start.
Anyone have similar issues?
It cranks fine, all fluids are topped up etc.

01-25-2013, 10:32 PM
It just sounds like your fuel pump is not delivering that gasolina where it needs to be. Do you prime it by turning the key to accessory position for a couple seconds first? It makes a distinct noise.

Purchase a new fuel pump from a vendor online. This is a ~$160 fix.

01-25-2013, 11:02 PM
I have a new one VDO if you need one ;)

01-26-2013, 10:06 AM
I think the problem is that it won't start when it doesn't prime, I have only noticed the buzz noise when it will start, don't think it is the fuel pump, it is whatever sends the signal for it to prime as when it does it starts ok

01-26-2013, 10:20 AM
That buzzing sound is an indicator that your fuel pump is working. If there are times that you don't hear that buzzing, and you clearly indicated that it won't start when you don't hear it, then i think it may be your fuel pump as well. Either that or some kind of bad connection leading to the pump?

01-26-2013, 12:22 PM
Ok, I'll check out the connections and clean them up

01-26-2013, 02:41 PM
If your fuel pump hasn't been replaced recently, then change it and your fuel filter. The pumps regularly fail between 150 and 200k km, or 10 years.