P2459 - DPF Regen Frequency - Dealer recommends replacing thermostat for $1100!

ReallyBigAir

Member
Joined
Dec 24, 2019
Location
The Queen City
TDI
2013 Passat TDI SEL Premium
Hello TDI'rs,

I've gotten the code - P2459 a couple of times and recently mentioned it to the dealer when I had the car in for a replacement clock spring. The dealer did a diagnosis and "recommended" replacing the thermostat @ $1100 for the parts and labor. Oh, and of course they charged me $119 for the diagnosis.

The car runs fine. During normal driving the water temp gauge indicates straight up - 190 degrees. Heater/defroster work fine. No obvious signs of a water temp issue. Currently, due to COVID shutdowns, most trips are short and I do hear regen happening pretty often. Also, the car consumes about a quart of oil every 900-1000 miles (oil consumption test performed twice by dealer, and they said it is within VM parameters).

Here's the text from the invoice:

"90200 scanned vehicle and found fault for regeneration too often. Performed test plan. Test plan informed me that the coolant values should match when the thermostat is open after 15 minutes. Upon waiting was not OK and that the thermostat may require replacement. Went further through the test plan and it checked various diesel systems including the upper and lower egr. Lower egr requires a certain coolant temperature otherwise it would not perform as like vehicles. During test plan the lower egr failed. Based on findings recommend replacing the thermostat. Customer declined repair (yes I did!) No repairs were performed for this concern."

What do you think? Based on this "diagnosis", would you replace the thermostat? Also, $1100 for parts and labor seems ridiculous for a thermostat replacement. I know it is a PITA on these engines, but WOW! I think it would cost less than $100 on most cars I've owned.

Feel free to chime in with any recommendations or thoughts. If there is a case for replacing the thermostat, could I DIY this with moderate technical skills and tools? What would be a reasonable charge from an independent mechanic?

Thanks in advance for any assistance or comments.....
 
Last edited:

AverageAndy

Active member
Joined
Sep 14, 2020
Location
Phoenix, AZ
TDI
2013 Passat
Also, the car consumes about a quart of oil every 900-1000 miles (oil consumption test performed twice by dealer, and they said it is within VM parameters).
I don't know a lot but this doesn't sound right. If my car consumed 1 quart per 1000miles I would be out of oil before even halfway to my next oil change! (assuming I didn't add any)
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis (where it's safe)
TDI
There are just too many to list....
Yep, thermostats are big jobs on those. Don't feel bad. Early VR6 Touareg thermostats are 12.1hr book time. Step one: REMOVE ENGINE. At least the CKRA engine in your Passat only has 4.7hr listed as book time. Although it still wouldn't be $1100 here. But it would still be about $800.
 

MukGyver

Veteran Member
Joined
Dec 11, 2020
Location
Sierra Ca
TDI
2004 Jetta PD bew
Hello TDI'rs,

I've gotten the code - P2459 a couple of times and recently mentioned it to the dealer when I had the car in for a replacement clock spring. The dealer did a diagnosis and "recommended" replacing the thermostat @ $1100 for the parts and labor. Oh, and of course they charged me $119 for the diagnosis.

The car runs fine. During normal driving the water temp gauge indicates straight up - 190 degrees. Heater/defroster work fine. No obvious signs of a water temp issue. Currently, due to COVID shutdowns, most trips are short and I do hear regen happening pretty often. Also, the car consumes about a quart of oil every 900-1000 miles (oil consumption test performed twice by dealer, and they said it is within VM parameters).

Here's the text from the invoice:

"90200 scanned vehicle and found fault for regeneration too often. Performed test plan. Test plan informed me that the coolant values should match when the thermostat is open after 15 minutes. Upon waiting was not OK and that the thermostat may require replacement. Went further through the test plan and it checked various diesel systems including the upper and lower egr. Lower egr requires a certain coolant temperature otherwise it would not perform as like vehicles. During test plan the lower egr failed. Based on findings recommend replacing the thermostat. Customer declined repair (yes I did!) No repairs were performed for this concern."

What do you think? Based on this "diagnosis", would you replace the thermostat? Also, $1100 for parts and labor seems ridiculous for a thermostat replacement. I know it is a PITA on these engines, but WOW! I think it would cost less than $100 on most cars I've owned.

Feel free to chime in with any recommendations or thoughts. If there is a case for replacing the thermostat, could I DIY this with moderate technical skills and tools? What would be a reasonable charge from an independent mechanic?

Thanks in advance for any assistance or comments.....
I had a car once used so much oil i never actually changed it. Just changed the filter periodically and kept adding to the fill line. :confused:
 

ReallyBigAir

Member
Joined
Dec 24, 2019
Location
The Queen City
TDI
2013 Passat TDI SEL Premium
Yeah guys, a quart per thousand miles is a PITA. Oil change interval is about 10K (per VW). So adding 9 quarts between oil change, at a cost of $75 in oil, really sucks. Had I known it could consume this much oil, and still be just fine with VW, I would have never bought it. I had 2 oil consumption tests performed by the dealer. They say a quart per thousand miles is within normal parameters. We checked for leaks, turbo oil leak, etc. Found nothing. All that oil is going somewhere. Makes me wonder if it is not contributing to the high regen frequency.
 

Tom in PT

Veteran Member
Joined
Jun 7, 2017
Location
Twilight Zone, WA State
TDI
2005 Passat sedan - SOLD; 2013 Passat DSG; both purchased new
"The On-Board Diagnostic (OBD) system, any malfunctions detected by the On-Board Diagnostic (OBD) system other than those related to the transmission."

Bingo!
 

ReallyBigAir

Member
Joined
Dec 24, 2019
Location
The Queen City
TDI
2013 Passat TDI SEL Premium

ReallyBigAir

Member
Joined
Dec 24, 2019
Location
The Queen City
TDI
2013 Passat TDI SEL Premium
Are you covered by the Extended Emissions Warranty still? If so this all should be covered including the diag fee. Also help to know where you are. The Queen city comes up for a number of various places.

Where does it state that the diagnostic fee is covered? Would like to avoid paying $119 every time my check engine light comes on due to DPF Regen frequency... I can clear it myself, but I would rather have VW pay the dealer every time. Might incent them to actually fix the cause of the check engine light coming on.
 

ReallyBigAir

Member
Joined
Dec 24, 2019
Location
The Queen City
TDI
2013 Passat TDI SEL Premium
"The On-Board Diagnostic (OBD) system, any malfunctions detected by the On-Board Diagnostic (OBD) system other than those related to the transmission."

Bingo!
Thanks Tom. I think I'll be calling the dealer and asking them to reach out to VW of America for "guidance". When they inevitably don't get proper guidance, I guess I'll be reaching out to VW of America myself.
 

Lightflyer1

Top Post Dawg
Joined
Sep 13, 2005
Location
Round Rock, Texas
TDI
2015 Beetle tdi dsg
Where does it state that the diagnostic fee is covered? Would like to avoid paying $119 every time my check engine light comes on due to DPF Regen frequency... I can clear it myself, but I would rather have VW pay the dealer every time. Might incent them to actually fix the cause of the check engine light coming on.
If it sets a check engine light for anything but the transmission, it is covered. No diagnostic fee for a covered event. Read and know that document if you want to get anything out of it. It is easier for them to say no if you are ignorant of what the court decree ordered to be done for the warranty. If you walk in there with no clue they will almost certainly say no. they usually say they will charge the fee but is removed if covered by warranty.

Are you only driving this vehicle on short trips? Please explain your driving routine. These cars really require owner participation in monitoring regens and ensuring the run and complete when needed. VAGDPF app is good for this.
 
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