BMW 328i Won't Start in Cold

My 2000 BMW 328i won’t start during cold mornings but it will start when its warm with no problem and it runs just fine at that time. If it is around 50 degrees and below it won’t start.

When I do get it started it idles up and down for the first 4 to 5 minutes while the car is parked. I have had the crank shaft position sensor replaced, the idle control valve, and the fuel pump relay. I still have the problem. Please help.

Who did the work so far ? A dealer ?

You should get your DME programming checked, if this correct you may have a VANOS problem. VANOS is the variable intake valve control and engages during engine warm up to optimize the fuel/air mixture.

VANOS is controlled by the DME programming sequence. Your problem likely resides with one of these 2 systems.

I agree with Scudder, the VANOS sounds like it could be the problem. The VANOS system normally activates in the high rev’s but also activates during cold starts to warm the car up more quickly. There are several gaskets/seals in the VANOS drive that wear out around 4-6 years of age. There is a kit available to redo those yourself if you are mechanically inclined, or the dealer should know about that problem. After replacing said seals, you should also regain some of that acceleration you may have noticed your car missing lately.

But, it could be something simpler. You didn’t describe the “won’t start” malady, but it could also be something as simple as a tired cold battery.

The car has 134,000, the battery is only about 1 year old. The car turns over like normal during the cold weather but it just won’t start. I have done some research and found that the problem could be the O rings around the vanos pistons. Its been hard convincing two different BMW mechanics that this could be it. They are checking the DME today. It is doing exactly what this article is describing.

It seems a lot of peole have trouble getting the dealer to admit to VANOS problems, let alone address them and fix them. so, if you’re up for it yourself(5-8 hours) here is the procedure:

And here is the kit(instructions on same page).

Sounds like you are on the right track even if BMW are in denial.

Thankfully my car is an old 88 M5 and avoids all of these problems - sometimes there’s a lot to be said for unsophistication.

I did a R 134 conversion on a 86-88 M5 the customer said he will pay whatever it cost. Cars are slightly rare. He really loved his car for reasons similar to yours,low level electronics. A normal e-39 (540i) blows its doors off.But the 540 is a good performer.

The conversion came out only medium,pressure levels were high and I never could get good air flow accross the condensor.

E-39 is a really nice car, but I have a thing for the old E-28 bodied cars and they give very little trouble with regular maintenance.

I had the DME reporgrammed 2 weeks ago and just had the ignition switch replaced. I still have the problem with the car starting in cold weather. On 3/22/09 it was 61 degrees outside and the car did not start on the 1st try and then on the second try it did. Will the vanos system actually keep the car from starting?

VANOS issues probably aren’t enough to keep your engine from starting once it gets warm out. If you keep having problems, try posting the problem on the vehicle specific site ( BMW 3 series cars). You’ll get the VANOS answer, because I think that will ultimately help the situation, but you may also get another gem of a suggestion.

As for why it didn’t start the first try, that happened to me once or twice when I thought I left the key in the start position long enough, but apparently I turned it back slightly to early. It could be that, it could be a whole list of things. Give the fanatics a try, see what you get. Make sure you search there first though, they get abrasive in posts about that.