A Little Update On My New M Coupe!!!

[tom_48]

Originally Posted by rcube

screw the modified CDV. Just give it time, you will get use to it.

Now I don't know what to do???

[enfield]

Change the CDV. You will get better with the smoothness of changes - specially 1-2. However, it will never be perfect. I changed my CDV after 1 year and I was used to it. However, even after a year there was a great change.
Dammittt is talking about 2 different issues. Firstly - The gear box is not very smooth. Mine became smooth after 15,000km. Secondly - Mine also refused to go into 1st one fine day. I have to put it in second for a second then go back to first and takeoff.
I would change the CDV even though you will get used to it. The CDV is 'supposed' to protect the transmission. However what it really does is shorten clutch life.

[rc'Z]

The gear change part of it seems fine in my lesser car, but, sometimes when doing the 1st to 2nd, it gets the 'bunny hop'. I know it is this stupid valve causing this, but it doesn't do it all the time. Sometimes it takes a good hard shift then again the 'hop'. Anyone know why it do and why it don't?

[155MPH]

I suggest you run out the gears longer. Shifting too soon is a sure fire way to get a jerky shift, especially in the low gears.

[tom_48]

Originally Posted by enfield

Change the CDV. You will get better with the smoothness of changes - specially 1-2. However, it will never be perfect. I changed my CDV after 1 year and I was used to it. However, even after a year there was a great change.
Dammittt is talking about 2 different issues. Firstly - The gear box is not very smooth. Mine became smooth after 15,000km. Secondly - Mine also refused to go into 1st one fine day. I have to put it in second for a second then go back to first and takeoff.
I would change the CDV even though you will get used to it. The CDV is 'supposed' to protect the transmission. However what it really does is shorten clutch life.

Thanks for all the info, man. Mine has only 9000 miles, but I'll change the CDV for sure.

[tom_48]

So for my M Coupe I should order this CDV? And also, is that the best website for those parts?

http://store.zeckhausen.com/catalog/...9cb3fc629f3426

[inTgr8r]

Originally Posted by tom_48

So for my M Coupe I should order this CDV? And also, is that the best website for those parts?

http://store.zeckhausen.com/catalog/...9cb3fc629f3426

Yes.. that's the ONLY source for the modified CDV.
The only other option is a complete removal.

[Hawkeye]

Originally Posted by tom_48

Thanks for all the info, man. Mine has only 9000 miles, but I'll change the CDV for sure.

You get conflicting views because some people, like Damnitt and myself, have driven enough with the CDV that we have gotten used to it... and if it isn't broken, don't fix it.

but I think I will change it anyway because it is so much different than my other car so switching between them feels weird.

[Dammmittt]

True...I have gotten used to it, but that being said, I'll probably do the CDV mod at some point.

The CDV shouldn't stop you from shifting into a gear tho. If you're used to the way the car shifts and the amount of time it takes for the clutch to engage/disengage, than changing the CDV will force you to relearn the car, although it probably wouldn't take too long.

So, if the issue is clutch feel and shift time, than get the zeck CDV. If the issue is random gear change refusals, either give it time, or try to get the gearbox changed under warranty.

I think the bottomline here is that the zeck CDV isn't going to hurt anything. But, will it fix your non-shift issues? Probably not.

[Nate2046]

Its funny, after a couple of test drives I really had no idea where you guys were coming from with this issue. Now that I've put 700 miles on my car I see the problem. I'm still not sure if the CDV is the source of the problem or if its just a combination of a really sensitive throttle and clutch engagement. I'm thinking I'll give it a couple thousand miles to see if I can adjust but yeah, its definitely different than any manual I've ever had.

Tom, are you getting more used to it, or is it still the same thing?

[tom_48]

Originally Posted by Nate2046

Its funny, after a couple of test drives I really had no idea where you guys were coming from with this issue. Now that I've put 700 miles on my car I see the problem. I'm still not sure if the CDV is the source of the problem or if its just a combination of a really sensitive throttle and clutch engagement. I'm thinking I'll give it a couple thousand miles to see if I can adjust but yeah, its definitely different than any manual I've ever had.

Tom, are you getting more used to it, or is it still the same thing?

Yes, I'm getting a little more used to it. Most of the time, I'm able to shift smoothly, but sometimes it gets a little rough. I think, I just have to have more patience with the clutch, and maybe later change the CDV.

[unScarred]

I just changed out the CDV with the zeckhausen part, and it definitely "feels" different... nice IMO feeling the clutch grab in a much more positive way related to releasing the pedal. Probably no way to tell if it's better or worse over the long term, just different for now in a way that I like... I do have less "jerky" starts, but I'm not ready to say that's the CDV change, I'm only 3000 miles into the car and moving between 3 very different cars driving so it's taking me a while to adjust.

[ianbiz]

Imagine if you had a roady

[Burt Reynolds]

Another Illinois M coupe- Congrats.

I vote for leave the CDV alone. It is much easier to get used to than learning to shift and AWD sports car smooth. Also, driveline work is not cheap...btw, clutches are cheaper than replacing other parts of the tranny. IMHO.

Cheers.

[plasmasmp]

The problem lies with the combo of the CDV and the electronic throttle that loves to change depending on your driving style. I still have my CDV, I will get rid of it at some point, but it can be really annoying.

I thought I was beginning to get terrible at shifting until I got back in my ancient beater and can shift and rev match it perfectly.

If I could just get the throttle to stop trying to adapt, that would probably fix most of the problem. Right now, in ether sport or normal mode, the throttle barely does anything for the first 3mm or so of movement, and then it has a non linear engagement (faster in sport) that would be fine if it were an automatic, but on a manual, can be a bear to live with some times.

[SunnyD]

Originally Posted by plasmasmp

The problem lies with the combo of the CDV and the electronic throttle that loves to change depending on your driving style. I still have my CDV, I will get rid of it at some point, but it can be really annoying.

I thought I was beginning to get terrible at shifting until I got back in my ancient beater and can shift and rev match it perfectly.

If I could just get the throttle to stop trying to adapt, that would probably fix most of the problem. Right now, in ether sport or normal mode, the throttle barely does anything for the first 3mm or so of movement, and then it has a non linear engagement (faster in sport) that would be fine if it were an automatic, but on a manual, can be a bear to live with some times.

+100000...That's exactly how I feel as well. The throttle is the reason that the car isn't smooth, but I'm going to go ahead and get the aftermarket CDV anyway to see if that can improve things.

[tom_48]

Originally Posted by SunnyD

+100000...That's exactly how I feel as well. The throttle is the reason that the car isn't smooth, but I'm going to go ahead and get the aftermarket CDV anyway to see if that can improve things.

Yeah, I think I'll take my odds and replace the CDV on mine, too.

[sixspeed]

Originally Posted by plasmasmp

The problem lies with the combo of the CDV and the electronic throttle that loves to change depending on your driving style. I still have my CDV, I will get rid of it at some point, but it can be really annoying.

I thought I was beginning to get terrible at shifting until I got back in my ancient beater and can shift and rev match it perfectly.

If I could just get the throttle to stop trying to adapt, that would probably fix most of the problem. Right now, in ether sport or normal mode, the throttle barely does anything for the first 3mm or so of movement, and then it has a non linear engagement (faster in sport) that would be fine if it were an automatic, but on a manual, can be a bear to live with some times.

I've never noticed any difference in throttle response on my M, apart from when you switch between normal and 'Sport' modes.

The throttle is perfectly linear, if someone over sensitive (too light a pedal?). I'm happy to say that, in my opinion, the problem is purely down to the CDV.

I never use the Sport mode btw. It's simply makes the pedal too responsive at light throttle openings...

[bosstones]

Originally Posted by Burt Reynolds

Another Illinois M coupe- Congrats.

I vote for leave the CDV alone.

+1 and +1

Originally Posted by sixspeed

I've never noticed any difference in throttle response on my M, apart from when you switch between normal and 'Sport' modes.

The throttle is perfectly linear, if someone over sensitive (too light a pedal?). I'm happy to say that, in my opinion, the problem is purely down to the CDV.

I never use the Sport mode btw. It's simply makes the pedal too responsive at light throttle openings...

Yeah, the throttle is quiet sensitive in Sport mode. I love it though. I drove the ///M to work most of last week and kept it in Sport both ways. A bit overkill in residential areas but a blast everywhere else! Like the shifter (notchy), clutch + CDV, Sport just takes some getting used to. I barely have to feather the throttle when coming off the clutch to get in gear smoothly.

[Andrewinla]

This weekend at the LA AutoX I drove a M Z4 Roadster with the CDV modified..I now am a beleiver.
It was so much easier to shift.

I have about 6K miles on my car and am used to it.
But just driving in the parking lot with the modiefied car was better.

[ersin]

Originally Posted by tom_48

Yeah, I think I'll take my odds and replace the CDV on mine, too.

How many miles are on the car? Have you gone through the 1200 mile service? If not, I'd suggest waiting for a couple thousand miles. In my experience the shifting gets better in BMWs after a few thousand miles. Additional bonus: the engine gets stronger too.

If it is still hard to shift then try the CDV replacement. And if it still sucks you can always get a short-shift kit. A weighted shift knob also helps.