[chemdude]

Hi all,

This is my first post in these forums and concerns my '11 335d I purchased in Nov. 2010 (04/10 build date). This is my first BMW and follows a Benz ('04 C230 Kompressor sedan that I originally purchased new, whose transmission died at ~65k miles due to a radiator leak into the transmission; Mercedes acknowledged the problem but only paid for half of the repair) that turned into a total money pit.

Two questions:

1) Since I purchased my car, I have noticed that there is a small drop in RPMs upon lighter but constant throttle, possibly as the torque converter locks into second gear (typically between 15 and 20 mph). This occurs in both D and DS modes. Under harder acceleration, there is either a drop or pause at anywhere between ~2,000 and 2,500 depending on how far the throttle is depressed, prior to continued increase of engine speed or gear change. Is this normal? As would be implicit from experiencing a failed transmission, I am suffering a bit of OCD regarding anything that could be slightly out of whack with the way the car drives. I have asked my service advisor, who after consulting with the shop foreman, claimed this is how the ZF transmission works and that no codes were showing on my car. Below is a video of the tachometer video showing the RPM 'blip' at ~4-5 secs. If there is more information I can provide, please let me know.

2) I have read several forums mentioning the SES light relating to the SCR metering unit (bmw p/n 18-30-7-807-206), and it seems like this may be an sporadically occurring problem. The light came on at ~1300 miles and then turned off a few days later when I brought it in for service. I drive ~50 miles/day. I took it in for service when it illuminated again for a few days at ~3800 miles and the part (as per invoice) was replaced. I'm now at 6,000 miles and the SES light has re-illuminated. Are others experiencing this frequency of problems? Before flaming me for posting this specific question here, if it is better to follow in a different thread, please delete this second question, and I will repost in the appropriate thread.

[WWONG]

If there is an SES light, there should be a code....

[chemdude]

Absolutely, I understand that there is now a code. I'm wondering mainly about a) if others experience a similar transmission 'blip' as described and b) how frequently other 335d owners are seeing their SES lights illuminate.

Thanks!

[cssnms]

Can't say that I have noticed that with my d, but it's so subtle I probably wouldn't notice and does not appear to be anything to be concerned about.

As for the valve, I recently took my car in to have the metering valve cleaned because my SES light popped on - car had 5k+ miles. The light did go out after a couple of days and before I took it to the dealer. However, the code was stored and the dealer cleaned the valve. So far haven't had a recurrance within the first 1k miles, only time will tell.

Also try posting your question on bmmerfest in the diesel subsection,,, seems to be a more active diesel crowd on there.

http://www.bimmerfest.com/forums/forumdisplay.php?f=154

[PJPHughes]

I've noticed it in my d, but only when I'm coming to a stop(tional) sign near my house and I accelerate from 3-5 mph. I believe it's just the car's tranny set up that starts the car in 2nd gear and the torque converter doing its thing. I will say the first couple of time, it did seem like the transmission was slipping...but now I'm used to it.

[Coolieman1220]

yeah maybe it is due to the lock up and 2nd gear take off. i'll pay attention to mine now and see if it does it as well. Our transmission is an excellent unit. It can lock up in all 6 gears and handle a lot of power with no issues as well as shift fast and smoothly. Same unit used with BMW V8 engines in the 7 series and such. ZF's 6HP28 unit i believe (or 26a)

I had to take my car in for the metering valve. They tried cleaning it but instead it needed to be replaced. After it was replaced I had the light illuminate once but then it went off a few days later before I could take it in. Phantom light maybe? not sure. Never bothered with it and its been off since. I also had a half power light come on for 2 seconds once too, that was scary to say the least. went away, no issues there.

btw Service Engine Soon only means something related to the emissions is wrong.

love this car, more and more each drive.

[chemdude]

Thanks for your responses! I've really noticed the second gear 'blip' (as per video) when I'm in stop-and-go traffic on the freeway in L.A. at ~15-17 mph. I did not notice this in a 335i M-sport loaner I had from the dealer a couple of times, but then it has a few differences (lower max torque tranny, gear ratios, etc) so it's not really the same.

I'm dropping my car off at the dealer for the SES light on Thursday to see what codes have been set. Will report back if anything different than the metering valve.

Thanks!

[pantherfan69]

i notice a pause when i floor it, it drives me crazy, especially when i am trying to make a turn with fast traffic coming! Usually turning off the DSC/DTC will allow me to accelerate like normal. I noticed the same thing on my 2006 non turbo 530i, i think its just BMW's way of trying to save the transmission from us accelleration junkies!

[username604]

Originally Posted by Coolieman1220

Our transmission is an excellent unit. It can lock up in all 6 gears and handle a lot of power with no issues as well as shift fast and smoothly. Same unit used with BMW V8 engines in the 7 series and such. ZF's 6HP28 unit i believe (or 26a)

Yup, i also believe its the same one that was used in the RS6 (although that was an awd variant )

[MrClean]

I have had three issues with my metering valve and two with EGR - car has about 18k on the clock.

[magungo]

I also have had numerous issues with the SES light. It does come on and go away. Sometimes longer than others. I'm taking mine in soon. The light was on for 2 days then went away. This will be my fourth time. I also have around 18k

[Karps]

I have a bit of a pause in mine on WOT from start but I always thought that was from the revised throttle mapping BMW programmed to prevent owners from smoking the tires with 425lb-ft of torque at every stoplight...

[Coolieman1220]

Originally Posted by Karps

I have a bit of a pause in mine on WOT from start but I always thought that was from the revised throttle mapping BMW programmed to prevent owners from smoking the tires with 425lb-ft of torque at every stoplight...

you are doing it wrong! launch her in second gear. first gear cuts throttle.

[F32Fleet]

No problems for me.