x3 - Tough start / rough idle

[Joe F]

My sister asked me to take a look at her x3. Apparently, it it is taking a couple of attempts to start and then is idling rough. What do I need to look at? I'm going to at least try to clean the MAF, anything else?

[kjboyd]

DONT TOUCH THE MAF!!! if you screw it up it will void the warranty!! what year?

[Joe F]

Got it, hand's off the MAF - thanks. It's an '06.

[kjboyd]

could have been a bad tank of gas. what kind and octane?
also, there are reports of this happening, and then letting the car rest and then starting again and it's just fine. I had issues with my 06 no starting right. there was an update for the 07s that did something similar, it may need a software upgrade.

[X3 Skier]

Happened a couple of times for a couple of days on my 05 X3 once but never again. Must have been water in the tank or something. 39000 miles so far with only that one instance.

Cheers

[Andrew*Debbie]

Got it, hand's off the MAF - thanks. It's an '06.

If it is an '06 and under 50,000 miles, it is still covered by a bumper to bumper warranty.

If it is under warranty, take it to a BMW dealer.

[OCNYBMW]

Mine gives some hard starts too. It is not consistent but seems to happen more when the car is hot. I do not think it is gas at all.

[AzNMpower32]

Likely a bad tank of gas. Drive it hard (aka redline) and/or put some Techron if you have not used Top Tier gas in a while.

I dunno about your opinions, but I think driving the X3 hard once in awhile, given proper conditions (like warmed up motor) is better than never exceeding 3000rpm.

[UncleJ]

Agree, probably bad gas. Take it to a dealer if it is under warranty to be sure if you feel it is something else. I have used Techron with good effect in other cars over the years and it might be useful here.

[OCNYBMW]

I always drive mine hard since it was new. It has 54K on it now. I will try some fuel system cleaner like Techron.

[sjampen]

I have a similar issue. It is the worst after letting the car sit for about 1 hr. I took it to a dealer and they told me it was the mass air flow meter, I changed it, but the problem is still there. I am taking it to another dealer next week. Lets see what they find.

I'll keep you posted.

Stephan,

[cnp55]

I've had this same thing ... it's not bad, but it's noticeable. Happens first start of the day when the car has been sitting out overnight. It's about 50 at night here at the moment. Worse if it's been raining and sitting for a day or two. 2006 X3 with 18000 miles.

Take it to the dealer? I'm pretty sure they won't be able to replicate it ... or is all the performance info coded into the infamous telepathic key?

[sjampen]

I took it to the dealer this week. It took them awhile, but they found the problem.

I had a leaking fuel injector. They replaced it, and now it starts very well.

Have the dealer check the fuel pressure. This will allow them to identify which injector is not working.

Stephan

[OCNYBMW]

Thanks Stephan. I did not think it was a bad gas issue.

I will take mine to the dealer too and see if it is a bad injector. BTW, how many miles do you have and what year is yours?

[sjampen]

Mine is a 2004 with about 91,000 Km (56,500 Miles)

I took it to Towne BMW in NY. The car was purchased from them used as a certified used car. The repair cost me only the $50 deductable.

Stephan