CDV test?

M_Six · 01-29-2009, 03:16 PM

Is there a way to tell if my 2006 3.0si still has the OEM CDV? The dealer has no record of it being swapped, but there is no telling if the original owner deleted it. It's small change if I buy a modified CDV and find out it's already been done, but if I can avoid the hassle...

Is there a specific point in shifting where you can readily tell the CDV is screwing things up?

MVF4Rrider · 01-29-2009, 04:21 PM

I would say 99% of owners don't make this change (cheap bastards), so odds are it's OEM. You can't tell by looking at it, but for sure I could tell by driving it. In addition, the modified part isn't available through BMW, so why would they have record of it? Typically, you don't want BMW to know you changed it.

Mikewarlover · 01-29-2009, 05:19 PM

Quote:

Originally Posted by MVF4Rrider

I would say 99% of owners don't make this change (cheap bastards), so odds are it's OEM. You can't tell by looking at it, but for sure I could tell by driving it. In addition, the modified part isn't available through BMW, so why would they have record of it? Typically, you don't want BMW to know you changed it.

+1 Most people do not touch and wanna do anything with their Z hence the small amount of memeber we have on the forum. My opinion is that if your shift is very smooth now don't do anything about it and it won't maater if its modified or not. If its jerky its probabaly oem

Z4Kevo · 01-29-2009, 06:36 PM

Remove the CDV and look at it...then you'll know.

M_Six · 01-29-2009, 07:48 PM

Quote:

Originally Posted by Mikewarlover

+1 Most people do not touch and wanna do anything with their Z hence the small amount of memeber we have on the forum. My opinion is that if your shift is very smooth now don't do anything about it and it won't maater if its modified or not. If its jerky its probabaly oem

I was telling the sales rep during the test drive that it had been almost 7 years since I had driven a manual shift and he said he was surprised because it seemed I knew what I was doing. But I could see his head move back and forth out of the corner of my eye as I shifted, so I was grumbling to myself about how sloppy I'd become. Methinks a CDV delete is in my immediate future.

Thanks all.

Z4Kevo · 01-29-2009, 08:16 PM

Quote:

Originally Posted by M_Six

Methinks a CDV delete is in my immediate future.

Some people absolutely swear by the CDV mod/delete...me not so much...although it did improve the precision when shifting aggressively.

Here are things I have learned about driving the ///M smoothly even with the CDV removed...particularly when shifting non-aggressively in 1st and 2nd gears.

1) The ///M does not like to be granny-shifted and does not play nice with other cars when forced to launch at a snail's pace. If we launched the ///M as it was designed to be launched we would quickly be up the boot of the car in front of us. Argggh!

2) Never granny-shift over bumps...if you are trying to ease into 1st gear over bumpy roads you will get screwed. Your foot just can't be steady enough to compensate and you will bunny hop to some degree. If I have to launch easy over bumpy terrain I always use 2nd gear...much more forgiving. If you are dumping the clutch and getting on it then 1st gear over bumps is not an issue.

3) It is very common when launching (while trying to hold your speed in check for slower traffic ahead) to feather the clutch at about 90%-95% for a second or two before upshifting. This can lead to bunny hopping as well. For some reason there is a tiny little window of sensitivity at the top of the clutch range that can be a real nuisance when trying to control your horses in turtle traffic.

Launching from 2nd gear while in traffic seems to solve most of the problems.

jragan · 01-29-2009, 10:22 PM

FYI, as reported in another forum recently, BMW service techs have been alerted to check for missing or modified (specifically Zeckhausen) CDVs when diagnosing any clutch/transmission problems.

Starscream · 01-30-2009, 05:50 AM

there should also be a paint pen line on it from the factory,

Both my Z's had them including the M,
Just go under the car and visually see if the line is uniform or has been broken or isn't there

M_Six · 01-30-2009, 09:53 AM

I was wondering about that. So even though the CDV delete is supposed to prolong clutch life, BMW uses it as an excuse to not cover clutch/transmission failures? I guess it's a non-factory mod, so no surprise there.

MVF4Rrider · 01-30-2009, 10:14 AM

Quote:

Originally Posted by M_Six

I was wondering about that. So even though the CDV delete is supposed to prolong clutch life, BMW uses it as an excuse to not cover clutch/transmission failures? I guess it's a non-factory mod, so no surprise there.

Generally speaking, if you're the type driver that abuses his equipment, I'd consider leaving the OEM lock valve in place. Ultimately however, all BMWs can benefit from better clutches and shift mechanisms than OEM.

My first mod for my new JCW MINI once I get it is a shift kit as the stock shifter is super sloppy. At some point, I'll install a shift kit in my Z4 M too.

M_Six · 01-30-2009, 10:28 AM

I don't abuse my vehicles. I need them to last 150k miles or more. My X5 had 46k on it when I bought it in March '07. It has 110k now. The only repair has been the control arms and bushings last month at 103k.

I'll drive the Z4 as is for now and see if/how much the CDV interferes.

01-29-2009, 03:16 PM	#1
M_Six Free Thinker 16964 Rep 7,455 Posts Drives: 2016 MB GLC300 4matic Join Date: Jan 2009 Location: Foothills of Mt Level iTrader: (0)	CDV test? Is there a way to tell if my 2006 3.0si still has the OEM CDV? The dealer has no record of it being swapped, but there is no telling if the original owner deleted it. It's small change if I buy a modified CDV and find out it's already been done, but if I can avoid the hassle... Is there a specific point in shifting where you can readily tell the CDV is screwing things up?
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01-29-2009, 04:21 PM	#2
MVF4Rrider PCA, BMWCCA 102 Rep 2,058 Posts Drives: 997S, MV Agusta F4, E46 M3 Join Date: Apr 2008 Location: Las Vegas NV iTrader: (0)	I would say 99% of owners don't make this change (cheap bastards), so odds are it's OEM. You can't tell by looking at it, but for sure I could tell by driving it. In addition, the modified part isn't available through BMW, so why would they have record of it? Typically, you don't want BMW to know you changed it. __________________ '08 Carrera S 6MT Guards Red/Black ext leather, Carbon fiber pkg, sport exh, sport chrono +, PASM, Nav, Bose, 19" forged turbos, red tranny tunnel '07 MV Agusta F4 1000 R 1+1, Corse Red/Silver, RG3 race pipes and factory race ECU
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01-29-2009, 06:36 PM	#4
Z4Kevo Private First Class 85 Rep 168 Posts Drives: 2007 M Coupe Join Date: Sep 2008 Location: Republic of Texas iTrader: (0)	Remove the CDV and look at it...then you'll know. __________________ 2007 BMW Z4M Coupe \| Sapphire Black \| 19" ZCP Wheels \| Michelin PSS - 245/285 \| Carbon Leather Black Corners \| UUC Short Shifter \| ///M Racing Pedals \| OE Strut Brace \| LED Accents \| PEMP Android
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01-29-2009, 10:22 PM	#7
jragan Imola Lover 26 Rep 749 Posts Drives: 2007 Imola Red M Coupe Join Date: Jul 2008 Location: Fort Worth, Texas iTrader: (0)	FYI, as reported in another forum recently, BMW service techs have been alerted to check for missing or modified (specifically Zeckhausen) CDVs when diagnosing any clutch/transmission problems. __________________ His: RIP-"Ruby" *E86 ///M Coupe: Pics Track Pics Short Vids Long Vids Hers: 997-1 C4S*: Pics
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01-30-2009, 05:50 AM	#8
Starscream Colonel 135 Rep 2,120 Posts Drives: ///M Roadster + E92 335i 6MT Join Date: Dec 2007 Location: Park Ridge NJ + Windermere FL iTrader: (23)	there should also be a paint pen line on it from the factory, Both my Z's had them including the M, Just go under the car and visually see if the line is uniform or has been broken or isn't there __________________ Imola Red Roadster
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01-30-2009, 09:53 AM	#9
M_Six Free Thinker 16964 Rep 7,455 Posts Drives: 2016 MB GLC300 4matic Join Date: Jan 2009 Location: Foothills of Mt Level iTrader: (0)	I was wondering about that. So even though the CDV delete is supposed to prolong clutch life, BMW uses it as an excuse to not cover clutch/transmission failures? I guess it's a non-factory mod, so no surprise there.
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01-30-2009, 10:28 AM	#11
M_Six Free Thinker 16964 Rep 7,455 Posts Drives: 2016 MB GLC300 4matic Join Date: Jan 2009 Location: Foothills of Mt Level iTrader: (0)	I don't abuse my vehicles. I need them to last 150k miles or more. My X5 had 46k on it when I bought it in March '07. It has 110k now. The only repair has been the control arms and bushings last month at 103k. I'll drive the Z4 as is for now and see if/how much the CDV interferes.
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