Rough cold start - Club Touareg Forums
 1Likes
Reply
 
Thread Tools Display Modes
post #1 of 19 Old 03-29-2019 Thread Starter
Junior Member
 
Touareg: 2011 V6 FSI
Join Date: Mar 2019
Location: Tulsa, Oklahoma
Second Vehicle: Still looking
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
Rough cold start

I recently bought a 2011 V6 Touareg I've had it about a month. I took it in to the shop and had the plugs, coils, oil change, filters etc done. The car runs rough for about 30 seconds on a cold start and then it evens out. My mechanic hooked up the diagnostic to it and couldn't find the fault. He said as it progresses it will trigger the code and he can then correct it. Any idea what it might be? The Touareg is in excellent condition visually and mechanically, I'm just stumped by what this might be.

I will say, I love this car. I was originally looking for a Cayenne but when this Touareg popped up at $10-12K less than a Cayenne I pulled the trigger. Can't say I'd ever buy a Cayenne as this car IMO is just as good (Cayenne owners disagree) but, I've extensively driven both.
986Speed is offline  
Sponsored Links
Advertisement
 
post #2 of 19 Old 03-29-2019
Touareg Mechanic
 
TurboABA's Avatar
 
Touareg: 2014 V6 TDI
Join Date: Aug 2018
Location: KW, ON, Canada
Second Vehicle: VW 2
Posts: 936
Thanks: 1
Thanked 39 Times in 38 Posts
My first guess would be a fuel issue.... have him look over the fuel supply closely.... it almost sounds like the fuel pressure is lost due to a small leak or something...... how long have you driven it since? Does it act the same way if you shut it down and start it 1hr later, or only after a prolonged sitting?
TurboABA is offline  
post #3 of 19 Old 03-29-2019 Thread Starter
Junior Member
 
Touareg: 2011 V6 FSI
Join Date: Mar 2019
Location: Tulsa, Oklahoma
Second Vehicle: Still looking
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by TurboABA View Post
My first guess would be a fuel issue.... have him look over the fuel supply closely.... it almost sounds like the fuel pressure is lost due to a small leak or something...... how long have you driven it since? Does it act the same way if you shut it down and start it 1hr later, or only after a prolonged sitting?
Only after sitting over night. It's been doing this since I bought it. I didn't notice at the dealer because they had previously started it and moved it around before I arrived.

I looked more on the forum and it appears this isn't an isolated issue. Seems people are tight lipped about this issue but, a "software remapping on startup" is what I've read... I'm skeptical as to that answer.
986Speed is offline  
Sponsored Links
Advertisement
 
post #4 of 19 Old 03-29-2019
Touareg Mechanic
 
TurboABA's Avatar
 
Touareg: 2014 V6 TDI
Join Date: Aug 2018
Location: KW, ON, Canada
Second Vehicle: VW 2
Posts: 936
Thanks: 1
Thanked 39 Times in 38 Posts
So you've been driving it and it still hasn't thrown a CEL?
TurboABA is offline  
post #5 of 19 Old 03-29-2019
Touareg Guru
 
Touareg: 2006 V8
Join Date: Sep 2006
Location: Wytheville VA USA
Second Vehicle: 2004 V6
Posts: 3,259
Thanks: 150
Thanked 313 Times in 273 Posts
Garage
This might not be 100%, since you list a 2011, but this is one thing to check.

It might be 100% for your T3. I know it works for T1 and T2.

nickyt is offline  
post #6 of 19 Old 03-29-2019
Touareg Enthusiast
 
New2Tregs's Avatar
 
Touareg: 2011 V6 FSI
Join Date: Mar 2018
Location: U.S.A.
Second Vehicle: a bicycle
Posts: 353
Thanks: 6
Thanked 19 Times in 19 Posts
Garage
My '11 does the same thing. It's got new OEM plugs/coils/filter and recent oil change. Seems to be more rough/noisier on cold starts in warmer weather. Smoother/quieter cold starts in colder weather < 35° F.

Some people have said this is due to the engine working to build up the oil pressure. Not sure if this is the case or not.
I was leaning to the possibility of carbon build up on the back of the intake valves being the culprit.


.

Yes I have a Vag-Com cable and software. No it's not from Ross-Tech but works flawlessly
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
.
New2Tregs is offline  
post #7 of 19 Old 03-29-2019
Touareg Mechanic
 
TurboABA's Avatar
 
Touareg: 2014 V6 TDI
Join Date: Aug 2018
Location: KW, ON, Canada
Second Vehicle: VW 2
Posts: 936
Thanks: 1
Thanked 39 Times in 38 Posts
Cool

Quote:
Originally Posted by New2Tregs View Post
I was leaning to the possibility of carbon build up on the back of the intake valves being the culprit.


.
..... because you're running Summer carbon buildup instead of All Season carbon buildup? Or 30sec carbon since it goes away after?

Also, if people say it's due to oil pressure building up...... is the oil more viscous in warm weather or cold weather?

You guys should pull your plugs after the vehicles sit overnight to see if your cylinders smell like gas.... I'm suspecting leaky injectors.
What sort of milage are you at?
TurboABA is offline  
post #8 of 19 Old 03-29-2019
Touareg Enthusiast
 
New2Tregs's Avatar
 
Touareg: 2011 V6 FSI
Join Date: Mar 2018
Location: U.S.A.
Second Vehicle: a bicycle
Posts: 353
Thanks: 6
Thanked 19 Times in 19 Posts
Garage
Quote:
Originally Posted by TurboABA View Post
..... because you're running Summer carbon buildup instead of All Season carbon buildup? Or 30sec carbon since it goes away after?

Also, if people say it's due to oil pressure building up...... is the oil more viscous in warm weather or cold weather?

You guys should pull your plugs after the vehicles sit overnight to see if your cylinders smell like gas.... I'm suspecting leaky injectors.
What sort of milage are you at?

At least you gave another possible scenario to the problem rather than just being a Richard Cranium about other peoples theories.
Presently I have ~82K miles but the Treg has been doing it since I purchased it used with ~72K miles on the clock.


.

Yes I have a Vag-Com cable and software. No it's not from Ross-Tech but works flawlessly
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
.
New2Tregs is offline  
post #9 of 19 Old 03-29-2019
Touareg Mechanic
 
TurboABA's Avatar
 
Touareg: 2014 V6 TDI
Join Date: Aug 2018
Location: KW, ON, Canada
Second Vehicle: VW 2
Posts: 936
Thanks: 1
Thanked 39 Times in 38 Posts
Theoretically, a leaky injector would potentially cause a rich condition after sitting which could "clear up" as you guys are describing once the engine started and a few hundred cylinder explosions too place.... Smell your oil... I should stink like gas if this is severe enough.
TurboABA is offline  
post #10 of 19 Old 03-30-2019
Touareg Mechanic
 
Spiegelglatt's Avatar
 
Touareg: 2008 V8
Join Date: Jun 2015
Location: Canby, OR, USA
Second Vehicle: 2007 V6
Posts: 1,110
Thanks: 14
Thanked 100 Times in 99 Posts
Garage
This is a normal 3.6 VR6 FSI characteristic caused by the Homogeneous Split Catalytic Converter Heating Method-And no I didn't just make that up. This is described on page 37 of the 3.2 and 3.6 VR6 Self Study as:

"This system has the task of quickly heating the
catalytic converters to operating temperature for cold
starts.
Fuel is injected twice in a combustion stroke.
The first injection occurs in the intake stroke. This
creates an even distribution of the fuel/air mixture.
In the second injection, a small additional amount
of fuel is injected just before ignition TDC.
The late injection increases the exhaust gas
temperature. The hot exhaust gas heats up the
catalytic converter so that it reaches its operating
temperature faster."

During this cycle the engine will run a bit odd...which is normal. The plus side to all this is that there is no secondary injection air pump.

The most common way of describing this is that the motor can sometimes sound like it has an aggressive cam and can even erect forward or backward creep by being a bit rough. Note that there is also a different (and much deeper exhaust note (if you put your ear down there).
TurboABA likes this.
Spiegelglatt is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Club Touareg Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
2008 gas V6 won’t start in very cold weather fto 1982 General Maintenance & Repair 6 02-16-2019 02:31 PM
Rough Cold Start - Help JulieWoods Engine, Transmission and Exhaust 12 03-31-2018 12:57 PM
2012 Touareg TDI cold start problem cspin2802 Diesel (TDI) Engines | R5, V6, V8, V10, R50 TDI engines 7 02-09-2013 08:45 PM
New 2011 V6 runs rough at cold start. weston Gasoline Engine, Electric Hybrid and Powertrain | V6, V8, W12, FSI 10 02-23-2012 11:56 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome
 

VW Touareg News Delivered to your Email!

Stay up-to-date with Touareg news in your inbox.

unsusbcribe at anytime with one click

Close [X]