Running rough when cold driving

dudg

Member
Joined
Dec 13, 2013
Location
Southcentral MN
TDI
2013 Passat
The past several mornings when I leave home for work my 2013 TDI Passat will start knocking and running really rough at about 30mph. It will do this for about 20-30 sec and seems like it warms up enough and runs fine after that. Haven't noticed any fuel mileage decrease and it also starts and idles fine. Any idea of what to look at?
 

kydsid

Veteran Member
Joined
Apr 18, 2012
Location
Texas
TDI
2012 Passat
Scan for any stored codes for injector performance. Sounds exactly like a bad injector.
 

nord

Veteran Member
Joined
Mar 5, 2010
Location
Southern Tier NY
TDI
All turned back to VW. Now a 2017 Hundai Tuscon. Not a single squalk in 10k miles.
Very likely just the warmup cycle. Exhaust gets clamped down to increase cat temps. You'll feel the valve open and close for a short time. No worries.
 

aja8888

Top Post Dawg
Joined
Dec 25, 2007
Location
Texas..RETIRED 12/31/17
TDI
Out of TDI's
Very likely just the warmup cycle. Exhaust gets clamped down to increase cat temps. You'll feel the valve open and close for a short time. No worries.
I don't believe this is normal and not to worry about it. My Passat has never experienced this situation. I would recommend he scan the car for DTC's rather than say "don't worry".
 

ChadS99SVT

Veteran Member
Joined
Jul 17, 2012
Location
Parker, CO
TDI
2013 Passat TDI DSG
Mine does this as well.

I don't think it is acceptable for the vehicle to be stumbling through its warmup and I'm not convinced that's ALL it is.....however I have zero desire to dump any money into it and once it's warmed up and driven for about 2 min there is no issues.

If I was under warranty I would be taking it in. But I'm not.
 

hudsonian

Veteran Member
Joined
Oct 13, 2013
Location
Calgary, AB
TDI
2013 Passat Highline TDI
I have a 2013, mine used to do this all the time on warm up, the update VW did just before DieselGate that was for the turbo and emmisions has fixed it 99%. I think I have only had a couple of stutters since this was done.
 

dudg

Member
Joined
Dec 13, 2013
Location
Southcentral MN
TDI
2013 Passat
I don't believe this is normal and not to worry about it. My Passat has never experienced this situation. I would recommend he scan the car for DTC's rather than say "don't worry".


Kind of agree, I've driven it 48,000 miles and it just started doing this.
 

Sigp232

Veteran Member
Joined
May 15, 2016
Location
California
TDI
13 Passat
Hi everyone Newbie here. Had same problem at 45000 miles on my 13 passat. But on mine after awhile my CEL came on and light came on exactly when fuel reached 1/2 tank not when it was full or 3/4 full. Drove it to dealer next day they checked it out and did a fuel test and said i had put bad diesel somewhere. I didn't agree with them cause my 250 ford diesel has no problem from same station I use. So they told me they would send fuel to an outside company for testing. After 3 days fuel test came out good. So there testing gizmo was flawed. Kept my car for another 3 days until they finally found out from VW headquarters that one of the injectors was bad. They replaced all injectors under the powertrain warranty 5 years or 60k miles. Car runs great now no more knocking noises when engine is cold.
It's your injectors take it in now since your still under warranty.
 
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ChadS99SVT

Veteran Member
Joined
Jul 17, 2012
Location
Parker, CO
TDI
2013 Passat TDI DSG
Hi everyone Newbie here. Had same problem at 45000 miles on my 13 passat. But on mine after awhile my CEL came on and light came on exactly when fuel reached 1/2 tank not when it was full or 3/4 full. Drove it to dealer next day they checked it out and did a fuel test and said i had put bad diesel somewhere. I didn't agree with them cause my 250 ford diesel has no problem from same station I use. So they told me they would send fuel to an outside company for testing. After 3 days fuel test came out good. So there testing gizmo was flawed. Kept my car for another 3 days until they finally found out from VW headquarters that one of the injectors was bad. They replaced all injectors under the powertrain warranty 5 years or 60k miles. Car runs great now no more knocking noises when engine is cold.
It's your injectors take it in now since your still under warranty.
If it was an injector wouldn't the problem be persistent no matter what the operating temp was?

I have zero symptoms after the car reaches say 100f.
 

jrm

Veteran Member
Joined
Jul 24, 2013
Location
Oregon
TDI
2013 Passat SE with nav (totaled)
Take a video and post er up :) sounds normal to me too, Its just the emissions system warming up by increasing back pressure and firing the injectors at different timing vs when warm.
 
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Sigp232

Veteran Member
Joined
May 15, 2016
Location
California
TDI
13 Passat
My car would run fine and no noise or rattling from engine after car got warmed up. Only use to happen when it would sit overnight or when engine was cold. And it doesn't get to cold in LA. Dealer had my car for 2 weeks a month ago bill came out to $1500 which VW covered under powertrain warranty. Now no issues at all when car first starts up in morning no rattling or noise. Let it warm up 2 minutes and I'm off to work. But I don't push hard either till it fully warms up.
 

c-wagen

Veteran Member
Joined
Oct 4, 2012
Location
Houston TX
TDI
North American Passat 2012 TDI SEL (bought back march 2018)
Sigp232, could you tell us what wes fixed? Injectors?
 

AJM

Active member
Joined
May 14, 2013
Location
Nashville
TDI
A6
I had the same issue with sputtering when cold. I used some Liqui Moly Purge and changed the fuel filter at the same time. Now my Passat runs brand new again. BTW, I have 90,000 miles on my Passat. Good luck.
 

Sigp232

Veteran Member
Joined
May 15, 2016
Location
California
TDI
13 Passat
Dealer said one injector was bad so Headquarters told them to replace all injectors. No more rattling when driving away from my drive way. Before it would rattle when it was cold engine and when temperature went to normal it would stop rattling.
 

Sigp232

Veteran Member
Joined
May 15, 2016
Location
California
TDI
13 Passat
Dealer told me when engine was cold one injector wouldn't spray enough diesel but when it warmed up injector would perform fine and open up. That's what he explained to me I have no idea about engines especially diesel engines but I do take care and appreciate my cars more than my ex wife and my recently ex girlfriend. Wish I could of changed there mouths and attitudes like my dealer changed the bad injector. But cars are more important these days.
 

shrifty

Top Post Dawg
Joined
Mar 23, 2010
Location
Western PA
TDI
2015 Passat TDI SE
My 14 Passat is experiencing the same thing, they said it is most likely an injector but not sure which one. Not interested in replacing all of them at the same time. As I'm at 108K now, I'm a bit out of warranty. Think I'll take the gamble and continue running it, at least I now have a 3 year 24 hour roadside assistance in case it goes wrong.
 

mtbsteve

Well-known member
Joined
Dec 28, 2012
Location
N/A
TDI
2012 Passat TDI SE w/roof and nav
Has anyone tried running some type of injector cleaner? Mine has been had this type of issue or maybe lifter noise on cold startups. The noise goes away after it warms slightly, usually after a few minutes.
I try to avoid adding anything to the engine based on VW not recommending it and have only used a few "white" bottles in 2 out of the 5 winters I have had the car.
I used to use injector cleaner and other gasoline additives back in the 1990's on my gas cars a couple times a year and you could see a difference, mainly due to water in the gas and/or poor quality gas but still hesitate with the diesel.
 

kydsid

Veteran Member
Joined
Apr 18, 2012
Location
Texas
TDI
2012 Passat
My 14 Passat is experiencing the same thing, they said it is most likely an injector but not sure which one. Not interested in replacing all of them at the same time. As I'm at 108K now, I'm a bit out of warranty. Think I'll take the gamble and continue running it, at least I now have a 3 year 24 hour roadside assistance in case it goes wrong.
You dont have to replace them all. Even if there isnt a code for the specific one in the ecu it doesnt take much brain power to teouble shoot. I think dealers replace all of them because its quicker than going thru tge trouble shooting and learning procedure.
 

shrifty

Top Post Dawg
Joined
Mar 23, 2010
Location
Western PA
TDI
2015 Passat TDI SE
Has anyone tried running some type of injector cleaner? Mine has been had this type of issue or maybe lifter noise on cold startups. The noise goes away after it warms slightly, usually after a few minutes.
I try to avoid adding anything to the engine based on VW not recommending it and have only used a few "white" bottles in 2 out of the 5 winters I have had the car.
I used to use injector cleaner and other gasoline additives back in the 1990's on my gas cars a couple times a year and you could see a difference, mainly due to water in the gas and/or poor quality gas but still hesitate with the diesel.
I will try this and see what happens, what can it hurt? :)
 

shrifty

Top Post Dawg
Joined
Mar 23, 2010
Location
Western PA
TDI
2015 Passat TDI SE
You dont have to replace them all. Even if there isnt a code for the specific one in the ecu it doesnt take much brain power to teouble shoot. I think dealers replace all of them because its quicker than going thru tge trouble shooting and learning procedure.
That's what I figured, however I wasn't about to get into a 1K+ repair bill and no guarantee that it would work :(
 

plagasse3

Member
Joined
Dec 21, 2011
Location
SE Louisiana
TDI
2012 Passat TDI SEL Premium DSG Opera Red
My car would run fine and no noise or rattling from engine after car got warmed up. Only use to happen when it would sit overnight or when engine was cold. And it doesn't get to cold in LA. Dealer had my car for 2 weeks a month ago bill came out to $1500 which VW covered under powertrain warranty. Now no issues at all when car first starts up in morning no rattling or noise. Let it warm up 2 minutes and I'm off to work. But I don't push hard either till it fully warms up.
I had this same problem starting 3 weeks ago. Some cold starts were worse than others. It seemed like dirty injectors to me so I added some diesel injector cleaner to a tank. I ran almost the entire tank through the engine. Then the engine died and now will not restart.
Does anybody know whether a failed injector will disable the engine? 2012 Passat TDI SEL DSG 173K miles
 

kydsid

Veteran Member
Joined
Apr 18, 2012
Location
Texas
TDI
2012 Passat
Does anybody know whether a failed injector will disable the engine? 2012 Passat TDI SEL DSG 173K miles

Yes. If the ecu doesnt get a correct response from each injector it will prevent starting instead of allowing a short or other issue. Id check the injector connectors first. One might just be loose.
 
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