[BimmerDom]

When the car is left overnight in colder weather, the engine cranks and starts normally, but immediately starts to sputter like it is struggling to stay alive (300-600rpm), this lasts for about 10 seconds, or I simply give her some gas for 5 seconds and she calms down to a normal idle.

I have JB3, it does the same thing in stock mode or on Map3.

Any ideas (before I go through the whole "bring it back to stock to go to the dealer" thing.

[jpsimon]

I had a rough idle for a while, which eventually led to bad misfiring and was not drivable. I would describe what I had as "struggling to stay alive 300-600rpm" along with the misfiring.

It ended up being a failing injector, which eventually failed and threw misfire codes at it's worst.

[BMW_TT]

Originally Posted by jpsimon

I had a rough idle for a while, which eventually led to bad misfiring and was not drivable. I would describe what I had as "struggling to stay alive 300-600rpm" along with the misfiring.

It ended up being a failing injector, which eventually failed and threw misfire codes at it's worst.

I think mine is leaning towards this.

[pwrdbynel]

Mine did it for a while. Turned out it was bad gas. As soon as filled up with new gas it went away.

[bryce]

i also had this problem, it eventually threw a few hpfp related codes and the dealer switched out my hpfp. no problems since

[Shieldze1025]

Mine does it every now and then, sometimes it sputters then goes into limp mode instantly. Same thing with me, I give it a little gas and no problems at all.

I have a Gintani tune, but i dont know if its from that or not.

[usu335i]

I experienced something similar this morning for the first time. The car started right up without a long crank. But it immediately started to idle very rough and I got a half engine light on the dash. The car seemed to be idling higher than normal as well. I looked up the codes that took place and it was misfires on 1, 2, and 3. Is this my hpfp?

Also, to be noted, I'm having O2 sensor trouble after my cattless dp were installed. I have the O2 sim installed but I think I may need to replace 2 damaged O2 sensors. Could these problems be related?

[Ilma]

It's not the tune.......happens on all of them including stock.

As others have posted - probably the HPFP or injectors.

I don't get sputtering, nor the rpm drop, but I hate cold morning starts because the car does seem to thud a bit every now and then (which feels like a misfire to me).

I had my pump replaced about a year ago and even then, I didn't get any misfire codes....just fuel pump codes.

[boilator]

The same thing has been happening on my car. I have the latest software and since it was loaded to prime the fuel pump, it feels like it has flooded the engine. I have to tap the gas to get it to idle over a grand and then things settle down. Just today I experienced my first limp mode. I restarted the car and it was gone. I also had to drive for about two miles for me to get to a safe spot and park, boy did the car run rough. Felt like the engine was vibrating off it's mounts.

I think this new software sucks.

Lator

[BimmerDom]

Yup, mine when into limp mode after a second gear acceleration... talk about scary to drive under a limp mode. Fortunately, I got to my destination and the CEL went away once restarted, but I'm not going to push the engine until I have it checked

[RON1X]

yeah, i have had the exact symptoms and have read other threads that people are having the same problems and it seems that it is related to the new software. However, after complaining of it to the dealer twice, they did replace the hpfp. It is still there, so I don't know if it fixed the problem completely

my car never went into limp mode, I would just have to use some throttle and it would turn over.

[BimmerDom]

Yup, hpfp failure, I joined the club, where's my t-shirt??

[awei130]

looks like a symptom of the HPFP. Had the same issue before mine got replaced.

[02themax]

Had the same issues all 6 injectors replaced and low fuel pressure sensor. Car is back to normal.

[usu335i]

I've been having these symptoms as well. I get misfires on cylinders 1,2, and 3 every morning. Its the injectors for sure. I have an appointment at my stealership tomorrow morning. Wish me luck!!

[Shieldze1025]

OK cool this all makes sense. Im at ~65k miles and never had a HPFP replaced. I started getting long cranks and got the software update which blows. Terrible wastegate rattle and now every cold start the engine stalls and I get a half engine light.

Definitely taking it to the dealer.