How the Volkswagen Diesel Scandal Will Affect Your TDI's MPG Rating | Edmunds.com

Edmunds.com

How the Volkswagen Diesel Scandal Will Affect Your TDI's MPG Rating | Edmunds.com

VW owners are wondering how the diesel emissions scandal will affect fuel economy ratings for Volkswagen TDI cars.

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zman49

What will the impact be on the car's performance?

agentorange

"According to Edmunds Director of Vehicle Testing Dan Edmunds, Volkswagen TDI vehicles will likely get closer to their advertised EPA mileage estimates once a fix has been instituted."

Why is this so? Is the fix for NOx so inefficient that it kills mileage?

locke42

agentorange said:

"According to Edmunds Director of Vehicle Testing Dan Edmunds, Volkswagen TDI vehicles will likely get closer to their advertised EPA mileage estimates once a fix has been instituted."

Why is this so? Is the fix for NOx so inefficient that it kills mileage?

No, it's because the EPA mileage numbers were measured when the engine was tuned for lower emissions. When the engine was tuned for higher emissions and better performance (i.e. when they were out on the road and not in testing), they therefore got better fuel economy. So the days when diesels regularly beat their EPA mileage ratings are probably over.

piredon

I'd demand they buy the thing back. Resale values are plummeting as we speak, and the "fix" will reduce both power and mileage. No simple recall is adequate for something like this. Or, I keep the car and you give me several thousand dollars in compensation.

socal_eric

Our Cruze Turbo Diesel easily exceeds EPA numbers along with all the Dodge/Ram diesels my family has owned (1500 EcoDiesel and 2500 Cummins). Most other diesel owners can easily meet EPA numbers too and I don't think there is widespread fraud outside VW which was trying to get around having to implement a more costly hardware-based (SCR with DEF injection) solution. More likely the testing procedures compared to real world driving favors diesel engines and their inherently more efficient design.

southernca_vw

I bragged about how my TDI Passat exceeded the advertised MPG...won't be doing that for long. All the features I enjoy about this car (peppy kick, amazing gas mileage) will be modified. I'm sure there will be some sort of class action lawsuit...

arikinthecity

I have a 2013 Passau tdi.  My plan is to keep the car for many years. After the warranty I want to modify the engine ecu with a chip to tune it for less boost on the turbo to allow for more efficiency.  I plan on staying away from the recall fix for as long as possible to see how it affects others first.  This cat is designed for high miles and long term use to get a lower tco so I want to keep it for at least 10 years or 20.

jreitano

I believe VW was adding additional fuel at a different point in the stroke to quiet the engine. So as not to get too much diesel clanking while parked or stopped. Hence why they added the defeat software. They were purposefully making the car more inefficient to make it more acceptable to people used to gas engines. Now without that the engine will sound a bit more like a traditional diesel. But will probably get slightly better mileage as it's not burning extra fuel while stopped.