[zsapphire7]

Has anyone experienced this? I have no idea what it can be...

My car has been running fine since i've had it ~2 years. Yet starting yesterday morning, cold start the car would start up and misfire. I would shut it off and start it up and same thing. After 3-4 mins tho, once things are somewhat warmmed up it. Issues go away. I can stop and start up no issues.

Same thing happened this morning. Nothing changed on the car before yesterday. I drove it home, went to sleep, and suddenly these misfires that only happen at cold came up....

What could possibly cause this? exhaust leak? obviously its affected by temperature because there are no issues once its warmed up. It doesnt even need to be warmed up that much or for that long either.

Any advice would be much appreciated

[enrita]

you just need to change the plugs.

[joec500]

or Injectors....

[zsapphire7]

spark plugs are pretty much brand new, didnt change them that long ago. Injector i cant be sure because the misfires are for all cylinders... but i may start to notice a pattern over time. Its only been two days. Also... why would all issues go away as soon as temp warms up a little bit?

[scottp999]

Maybe you got some bad gas?

[Ilma]

Might also be the fuel pump.

Lumpy cold starts are one of the symptoms, and it literally appears overnight and then comes and goes.

Eventually the pump throws a code and fails.

[TriniJots]

I have these same problems for the last few days. I think it may be the spark plugs or the injectors, Im waiting for my SA to call me back. It seems recently this is becoming a big problem as a few of us on the forums are starting to experience this problem

[zsapphire7]

Originally Posted by TriniJots

I have these same problems for the last few days. I think it may be the spark plugs or the injectors, Im waiting for my SA to call me back. It seems recently this is becoming a big problem as a few of us on the forums are starting to experience this problem

How long have you had your car?

[TriniJots]

How long have you had your car?

Production was February 2009, purchased April 2009. January, BMW had the hpfp replaced and in February they replaced the spark plugs and updated the software.
Sunday is when I started experiencing this problem, I am hoping this problem can be resolved soon

[dzenno]

its your injectors...plugs have next to nothing to do with cold start issues..just got all 6 of mine changed but the dealership also changes the plugs at the same time AND they reprogram your car with latest software...in my case it was just a single injector that was bad (that I knew for sure) but they ended up replacing all of them

[zsapphire7]

oh my... i need to get my dme updated anyways. So injectors need to warm up more as they go bad hun? Btw what is the lifespan on injectors? Its a consumable item like spark plugs right?

[dzenno]

well they have a new part number (revised) so they should be better...one or more of your injectors is most definitely leaking gas into the cylinder and then in the morning when you start it up that cylinder with a bad injector will have a too rich of a mixture to start with (richer than others that didn't have a leak)...so in this case that cylinder will misfire and then as a chain reaction the other cylinders in the same bank will also misfire because of the car's software quickly leaning out the other cylinders in the bank

[GeorgiaTech335coupe]

6 new injectors (new part #), 6 new plugs, 2 new coils, 4 dealership visits and seafoam over 3 months and I am still the president of the cold start misfire club. Oh and I live in a very warm climate. Its been 70-80s here. On round #5 now.

[TriniJots]

Any idea on what to do since this throws no codes? Im going to be kind of upset if the dealer tells me, "theres nothing wrong, its a normal sound".

[Tiago@VRSF]

Can you describe this "misfire"?

[TriniJots]

http://www.e90post.com/forums/showthread.php?t=373781

The OP posted two youtube videos on that thread. Those would show you exactly what our problem is.

[nosey]

do u have long cranks too?

I had long cranks and which were also sometimes associated with rough idling (due to misfires) Just got my car back from the dealer...they said it was the hpfp which they replaced...cleared the codes and updated the software...

everything seems back to normal so far...we'll see how long this will last

hopefully ill never get this problem again...

[e90_guy]

I've the exact same problem 2 weeks ago. The problem is caused by a bad fuel injector in one or more cyclinders

[stealth-twntrbo]

I just had my HPFP replaced 2 weeks ago and got the new software update to my DME, I also had one injector replaced and 2 plugs replaced. I am also having misfires during cold-starts and it goes away when the car gets warm and seems to run fine, I feel as if possible another injector is going bad. I did just put downpipes on the car and I wonder if that would contribute to these cold start issues. I think I have an injector issue most likely I think i am going to call the dealer again. I am curious to what maybe causing this.

[zsapphire7]

its definately a misfire issue since it does cause that misfire code. I think it maybe isolated to a cylinder. a few more days and ill figure out exactly whats causing it. My hunch because the spark plugs are relatively new, is that its the fuel injector for one cylinder. You guys are probably right

Im also runnign catless with no o2 sim at the moment so who knows... maybe thats contributing to it. Im just gonna test it for a few days since it really only happens in the morning at first start i can only see what happens once a day.

[TriniJots]

Just took my car into BMW, they are going to look into the misfires. I took out my JB3 and wiped the codes, Im a bit nervous to see if they find out it was in

[zsapphire7]

Originally Posted by TriniJots

http://www.e90post.com/forums/showthread.php?t=373781

The OP posted two youtube videos on that thread. Those would show you exactly what our problem is.

Im pretty sure that thread is a totaly different issue. For him it only happens after warming up. Mine only happens when its cold. After its warmed for 3-5 mins, the car runs as if there was no issue before. I can drive it around like it never happened for the day.