VW's Emissions Retrofit May Be Among Costliest

[PandaBear]

Originally Posted By: Brybo86
Originally Posted By: MrHorspwer
Originally Posted By: Brybo86
What kind of person would bring their VW TDI in for this "service" ?


People who live in an area that requires a regular emission test or inspection...

People who live in an area that requires an annual inspections for registration that involves checking for open recalls...

People who live in an area where it is required to have all recalls completed before selling the vehicle...


never heard of that.
I sell my car to my neighbor who checks for recalls? how is that enforced?



That happens on my IS250 last year. They force you to send in a work completion form that the dealer has to sign off and send it in with your registration renewal.

 

[PandaBear]

Originally Posted By: spackard
In Europe, part of the fix for the 1.6 and 2.0 diesels will be a passive labyrinth to help create laminar flow across the MAF.

http://autoweek.com/article/vw-diesel-scandal/vw-reveals-diesel-fix-16-and-20-liter-engines-europe

It'll be interesting to see if the fix is that simple for the US models.


So if I understand correctly, they are updating the code to run the engine richer by 1) updating the fuel map and / or 2) increase resistance thus increase the vacuum when the measurement is not accurate at idle.

That'll work at the expense of fuel economy, obviously cheaper to install than urea injection.

 

[artificialist]

Originally Posted By: PandaBear
Originally Posted By: spackard
In Europe, part of the fix for the 1.6 and 2.0 diesels will be a passive labyrinth to help create laminar flow across the MAF.

http://autoweek.com/article/vw-diesel-scandal/vw-reveals-diesel-fix-16-and-20-liter-engines-europe

It'll be interesting to see if the fix is that simple for the US models.


So if I understand correctly, they are updating the code to run the engine richer by 1) updating the fuel map and / or 2) increase resistance thus increase the vacuum when the measurement is not accurate at idle.

That'll work at the expense of fuel economy, obviously cheaper to install than urea injection.

I see those flow straighteners in many GM engines that use mass air sensors. I'm surprised VW didn't think of using them earlier.

I doubt the flow straightener will have much impact on MPG. From what I gathered, the cars were producing high NOx, and to get less NOx you have to increase EGR flow and that always hurts the fuel effeciency of a diesel. This is one reason why the Ford PSD 6.4 (No DEF) had far less fuel economy than the Ford PSD 6.7 (uses DEF)

 

[supton]

I didn't feel like reading the link, sorry. Why would they need to alter the tubing? My old Jetta had an intake flap--looked identical to a throttle plate, but as a diesel it wasn't for "throttle". It was to choke off the engine during times of high EGR "need". IIRC the newer TDi's have some sort of similar exhaust valve too?

So, my question is, did they ditch the intake flap on the common rail TDi's when they redid their EGR system?

 

[rslifkin]

Originally Posted By: supton
I didn't feel like reading the link, sorry. Why would they need to alter the tubing? My old Jetta had an intake flap--looked identical to a throttle plate, but as a diesel it wasn't for "throttle". It was to choke off the engine during times of high EGR "need". IIRC the newer TDi's have some sort of similar exhaust valve too?

So, my question is, did they ditch the intake flap on the common rail TDi's when they redid their EGR system?


I think they went to a flap in the exhaust to generate backpressure. Serves pretty much the same purpose though.

 

[artificialist]

The 7.3 PSD had a backpressure generating valve on it, my understanding was not that it increased EGR flow, but it forced the engine to reach operating temperature quicker.