Check Engine Light 2009 Jetta TDI

bhunt70

Member
Joined
Jul 18, 2009
Location
Virginia
TDI
none
So my CEL came on a month or so ago. I took it to my local vw place to get them to run the codes, I had a coupon and it was free. I told them to let me know what the problem was since I was going to take it to one of the trusted mechs listed on this site.

The say it was my catalytic converter and replaced it free. Two days after I got it back the CEL came on again. Called up vw, they replaced a sensor free again. No problems until yesterday, the light came on again. Should I try vw again or try to find a mechanic that can correctly diagnose and fix the problem.

I only have 20k on the car, its my night and weekend car. I know I need to drive it more.
 

jessabug

Veteran Member
Joined
Jan 30, 2012
Location
Cary, NC
TDI
Hubby's 2001 Jetta TDI, '84 IDI turbo diesel Jetta
What are the actual codes that are coming up?
 

bhunt70

Member
Joined
Jul 18, 2009
Location
Virginia
TDI
none
I was never told, I'll check the paperwork when I get home but I'm pretty sure it's not listed. I assumed they were pointing to the problems they fixed at first, now not so much.
 

JSWTDI09

Top Post Dawg
Joined
Jan 31, 2009
Location
Las Vegas, Nevada
TDI
2009 JSW TDI (gone but not forgotten)
A couple of points:

1) Find someone near you with VCDS and find out what the actual fault codes are. We can be more helpful then.
2) I would stick with a dealer as long as you are under warranty. However, you might want to see if you can find a dealer near you with a better service department. Many VW dealers have poor service departments, but not all of them.
3) Once your warranty is over, stay away from dealers, unless it is to buy parts (like wiper blades, etc.).
4) You need to take it out onto the highway and put some miles on it, at least occasionally. TDIs like to be driven and they have nothing against being driven hard. Exercise is good for your car just like it is good for you.

I was never told, I'll check the paperwork when I get home but I'm pretty sure it's not listed. I assumed they were pointing to the problems they fixed at first, now not so much.
If you are not told what the codes are - Ask what they are and demand an answer!

Have Fun!

Don
 
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oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
We can't offer much help unless we know what DTC(s) caused the MIL to come on in the first place.

The exhaust system on that car is FAR more complex than just a "catalytic converter", so it is possible what they told you they replaced was actually something altogether different.
 

Ol'Rattler

Top Post Dawg
Joined
Jul 3, 2007
Location
PNA
TDI
2006 BRM Jetta
Some dealers don't really troubleshoot, they just throw parts at a problem until the problem goes away or your warranty runs out.

A DTC (code) doesn't magically tell you what part to change like some techs believe. A good tech will use a DTC as a place to start in diagnosing what the actual problem is.
 

bhunt70

Member
Joined
Jul 18, 2009
Location
Virginia
TDI
none
A code on the first of my invoices was P0420, catalyst efficiency below threshhold. They changed part 1K0-254-401 (catalyst) and 1K0-253-725 which was the clip.
The second they said "see previous history" and fixed my exhaust gas temp sensor because it shorted.
 
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JSWTDI09

Top Post Dawg
Joined
Jan 31, 2009
Location
Las Vegas, Nevada
TDI
2009 JSW TDI (gone but not forgotten)
A code on the first of my invoices was P0420, catalyst efficiency below threshhold. They changed part 1K0-254-401 (catalyst) and 1K0-253-725 which was the clip.
The second they said "see previous history" and fixed my exhaust gas temp sensor because it shorted.
Very interesting. I checked several VW dealer's parts sites and they all agree that p/n 1K0-254-401 does not exist. The clip exists, but the catalyst does not. Are you sure you got that part number right?

Have Fun!

Don
 

bhunt70

Member
Joined
Jul 18, 2009
Location
Virginia
TDI
none


If this picture works those are the two codes. If not, I think I got the numbers right but maybe I put O instead of 0. Or vice-versa.
 

Joe_Meehan

Top Post Dawg
Joined
Sep 3, 2005
Location
Ohio USA
TDI
NB TDI, 2002.5, Silver


If this picture works those are the two codes. If not, I think I got the numbers right but maybe I put O instead of 0. Or vice-versa.

Note the code should be in the format of PXXX where XXX are numbers 0-9.
 

tdiatlast

Top Post Dawg
Joined
Jan 21, 2009
Location
Fort Worth, Texas
TDI
2009 Sportwagen (boughtback); 2014 Passat TDI SEL (boughtback)
09? I thought the cat convertor/exhaust/DPF was all one unit?

OP: Please put your year/model in your signature...I see it's in the thread title, but it's easier to reference if it's in your sig....
 

Joe_Meehan

Top Post Dawg
Joined
Sep 3, 2005
Location
Ohio USA
TDI
NB TDI, 2002.5, Silver
That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.
 

JSWTDI09

Top Post Dawg
Joined
Jan 31, 2009
Location
Las Vegas, Nevada
TDI
2009 JSW TDI (gone but not forgotten)
09? I thought the cat convertor/exhaust/DPF was all one unit?
In the '09 models the DOC (Diesel Oxidation Catalyst) and the DPF are one unit, but this is not the only catalyst. There is also the NOx Storage Catalyst and the H2S catalytic converter. These last 2 are downstream from the DOC/DPF unit (under the car). Therefore, there are actually three "catalytic converters" in our cars. We have no idea which "catalyst" they replaced or what sensor they replaced. This mystery will continue until we either see DTCs or correct part numbers of the parts replaced. Of course, the parts replaced so far have (apparently) not yet fixed the actual problem, so the story continues....

Have Fun!

Don
 

bhunt70

Member
Joined
Jul 18, 2009
Location
Virginia
TDI
none
That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.
I did post it above... P0420. I've taken the car to Advance Auto when it first started, they gave me a generic answer since they don't run the specific VW software. Thanks.
 

bhunt70

Member
Joined
Jul 18, 2009
Location
Virginia
TDI
none
Wow, I hope your waranty is nice and long! I could see if it was high milage.

Randy
Sadly I think this is my own doing for not driving it enough. Maybe its time to turn in the work truck and drive the car for work too.
 

MacBuckeye

Veteran Member
Joined
Nov 11, 2008
Location
North Carolina
TDI
2009 Jetta
P0420 and P1951

Today I get both P0420 and P1951. Appeared to have happened right after a regen. I cleared both codes, but they both came back.

? for you...
Is this the exhaust flap or sensor?
I'm going with a DPF delete at the end of the month. Can I just wait or is this going to cause me some bigger problem? What about future regens?

With 139K miles, should I look at replacing my cooling fans?

Car runs fine that I can tell. Normal operating engine temps. Fans are working that I can see. I assume after a DPF delete that there will be fewer fault codes since they will no longer be functioning/connected? (i.e. deleted)
 

JASONP

Top Post Dawg
Joined
Feb 24, 2008
Location
Guelph
TDI
2015 Golf TDI Comfortline 6spd
Today I get both P0420 and P1951. Appeared to have happened right after a regen. I cleared both codes, but they both came back.

? for you...
Is this the exhaust flap or sensor?
I'm going with a DPF delete at the end of the month. Can I just wait or is this going to cause me some bigger problem? What about future regens?

With 139K miles, should I look at replacing my cooling fans?

Car runs fine that I can tell. Normal operating engine temps. Fans are working that I can see. I assume after a DPF delete that there will be fewer fault codes since they will no longer be functioning/connected? (i.e. deleted)

http://wiki.ross-tech.com/wiki/index.php/16804/P0420/001056


Sent from my POS iPhone 4S
 

MacBuckeye

Veteran Member
Joined
Nov 11, 2008
Location
North Carolina
TDI
2009 Jetta
JASONP- thanks for the info / link. I'm hoping I can go another couple weeks. Going with a DPF delete & tune toward the end of the month. Ever since my turbo failure back in March and 2 turbo replacements later, I can't catch a break. Had the lovely P00AF code after my turbo issues. Took dealer forever to diagnose and fix.
I firmly believe my exhaust system took a big hit when my turbo crapped out and engine oil got into the exhaust system causing ugly grey/white smoke out the tail pipe. Wouldn't be surprised if the sensors got damaged and the DPF is on the verge of dying.
Quick question, as far as possible causes, what/where exactly would be the "leakage in intake" be? Intake manifold? Or intake somewhere else? I also had the intake manifold replaced due to the intake manifold flap going bad. Is the P0420 being caused by the intake manifold?
Sorry guys, my engine knowledge kind of stops at the oil change, fuel filter, DSG flush, and brakes maintenance skill level. :D
 

JASONP

Top Post Dawg
Joined
Feb 24, 2008
Location
Guelph
TDI
2015 Golf TDI Comfortline 6spd
It could be the intake flap failure but by looking at the description of the code, it seems to be more related to 1.8T gassers than tdi . Or. As you stated te dpf is getting clogged simulating air restriction on intake, who knows??? Just taking a stab at it ....


Sent from my POS iPhone 4S
 

MacBuckeye

Veteran Member
Joined
Nov 11, 2008
Location
North Carolina
TDI
2009 Jetta
My biggest concern right now is how long (how far) can I drive with the P0420 fault code? Does anyone know if the car will regen with this code? I'll soon find out I guess.

Both fans are turning on when I turn on the AC. Not sure why I still have the fan fault code P1951. Unless the sensor to turn the fans on during a regen or to turn the fans on under high engine temps. Otherwise, both fans are coming on. At least when I turn on the AC.

Counting down to my DPF delete, Malone Tune, and DSG tune.....
 
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