Cold engine start choppy/laggy throttle, ICV?

[Transfer]

Does anyone else notice their engine is rough just below 2000 rpms when cold? I'm the second owner on my E90 so I'm not sure if it's always done this but it hasn't changed in my 1.8 years of ownership. When giving throttle input on a cold start, there is a noticeable hang right before 2000 which can cause some serious jerkiness. It happens in neutral or in gear so the transmission isn't involved and it goes away when warmed up.

With a smooth steady increasing throttle input the revs climb to ~1600 or so then has almost a stalling like feeling for a 0.5-1 second then the revs jump up after 2000. Now that cold weather is back it's more noticeable again and it's annoying. My car is a late 2011 with 31k miles.

I also get a rare bouncing idle so makes me wonder if this is an ICV issue?

Here's a short video which sort of shows the issue. Throttle input is steady but you can see the lag and jump. The third rev shows it the best and you can almost hear a low tone lagging engine noise

[fsmtnbiker]

My car does the same thing (09 6MT). I haven't pulled the ICV out yet but that was my first thought as well.

It makes it very difficult to drive the car smoothly right after starting it cold. I notice if I let the car sit and idle for a couple minutes it doesn't have this issue at all.

No codes stored either.

[Transfer]

I wonder if there is any way to get my dealer to replace the ICV. It's not very noticeable but it certainly makes driving a little annoying for the first 5 minutes of my day.

[Ezio]

still under warranty ? maybe have dealership look at it

[fsmtnbiker]

Mine is far out of warranty (132k miles). I will probably pull the ICV after I get back from SEMA next week and see if there's anything notable (or just replace it.)

[0_to_60]

this happens to mine too, on others cars cleaning the throttle body and doing a relearning procedure fixed, but i dont know about the m3

[dparm]

I'm seeing the extremely low cold-start redline, so I assume you have a tune? Any chance it's related?

[Transfer]

Originally Posted by dparm

I'm seeing the extremely low cold-start redline, so I assume you have a tune? Any chance it's related?

No, it was there before the tune.

[KmndntKlink]

I had this problem too. Would fluctuate wildly from 500-1500 rpm and sounded like it was going to stall. It never did, mind you. I was told it could be the ICV as well. Thing is, it fixed itself right after the switch to winter gas. It's been really cold where I am and as soon as I burned off the remaining summer gas in my tank, startup smoothed out. Running BPM stage 2.

So maybe just see if it goes away on its own?

[fsmtnbiker]

My car is on the OE tune, recently updated from 170E to 240E. No change, this bog/hesitation existed before and after with no change. It seemed a little better when I changed plugs, but not fixed at all. I have also replaced the primary oxygen sensors as normal maintenance items, no change.

At this point there isn't much that would cause it, IMO:
-ICV
-MAP sensor problem (would likely throw a code)
-TPS problem (would likely throw a code)
-Plugged/Dirty Injectors (would likely cause oygen sensor/fuel trim codes)
-Throttle actuator problem
- ..??

I'll keep the thread up to date as I have time to work on a solution. My car is also a little "jumpy" at tip in, especially noticeable/irritating at low speeds in 1st gear. I believe the ICV is used to help smooth out this transition, so it's definitely #1 on my list for scrutiny.

[Mr. Liu]

Not sure if my situation is relevant to the ICV - but if I start driving right after I turn my car on, shifting from 1-2 then 2-3 the car kind of sputters and hesitates during shifts. (Sound is nore noticeable since I have a full exhaust) It sounds like he car is farting almost when normally its a clean shift.

[dparm]

OBD2 is ridiculously fickle, in my experience. In many different cars I've owned and driven, there are random cold-start transients that don't return with any pattern.

Until it throws a code, or driveability is severely affected, I would just keep driving the car and not lose any sleep over it.

[Transfer]

Originally Posted by fsmtnbiker

My car is also a little "jumpy" at tip in, especially noticeable/irritating at low speeds in 1st gear. I believe the ICV is used to help smooth out this transition, so it's definitely #1 on my list for scrutiny.

I definitely get that and I blame it on the throttle hesitation then surge right before 2k rpms. The car is certainly driveable but if I could make this go away, i would be very happy.

[rcracin]

This is normal with every manual car i've owned including obd0 cars.

[FormulaMMM]

Originally Posted by Transfer

Does anyone else notice their engine is rough just below 2000 rpms when cold?

Yes. Especially now that the cold weather is back.

Normal for M cars in my experience. Always been there with my E90, was the case in my E39, felt it in an E46.

If you're getting the bouncing idle, then you may also have the icv issue, but I don't think the rough engine characteristics you describe are necessarily related.

I have no bouncing idle issues, but she can be cranky until warmed up.

I know that indicates there is no need to wait and let the car idle before beginning to drive. However, I have noticed that whenever I take a minute or two before setting off, and the cold start sequence concludes, the engine is more smooth straightaway.

[fsmtnbiker]

I drove an '11 M3 back to back with mine today and confirmed that my car has *something* amiss. The other car was very smooth and nice on-off throttle at low speed and stable at idle. It also drove fine even when cold-started and driven immediately.

I ordered an ICV today - Should have it Friday. I'll report back if that makes any difference.

[serge]

Originally Posted by fsmtnbiker

My car does the same thing (09 6MT). I haven't pulled the ICV out yet but that was my first thought as well.

It makes it very difficult to drive the car smoothly right after starting it cold. I notice if I let the car sit and idle for a couple minutes it doesn't have this issue at all.

No codes stored either.

+1

Same issue with my '11 6MT and just 8k miles. The jerkiness is at times unbearable, unless I leave the car at idle for about 1-2 minutes, then the problem disappears.

[rev9k]

Originally Posted by fsmtnbiker

My car does the same thing (09 6MT). I haven't pulled the ICV out yet but that was my first thought as well.

It makes it very difficult to drive the car smoothly right after starting it cold. I notice if I let the car sit and idle for a couple minutes it doesn't have this issue at all.

No codes stored either.

that's totally normal..

All m cars I have driven and owned all do this when cold.

[fsmtnbiker]

Without going into a long explanation, it isn't normal. The other '11 I drove is normal - My car has something wrong. It bucks, hesitates, and 'chugs' at certain throttle angles at low RPM.

Swapped the ICV last week. No change on my car.

I'll probably log the car sometime soon on cold start and see what is going on.