3.0 TDI gen 2 PC group post-fix impressions

HerrK

New member
Joined
Dec 20, 2017
Location
Poway, CA
TDI
2014 Q5
We had the emissions repair completed on our 2014 Q5 TDI about 500 miles ago. The onboard milage computer shows about a reduction of about 4 mpg (combined city highway) in comparison to pre repair. The onboard system was previously optimistic by about 1.5 mpg. I'm doing an actual miles driven vs tank fill mileage check now for the next couple of tank fill ups. So will report back in a month or so. I don't really notice any noise or otherwise shift changes but then I don't tend to putt around chasing milage numbers like my wife. Still consider it one of our best vehicles especially since VW has now paid for the "diesel" engine upgrade and at least 50K miles worth of free diesel with their emissions reparations.
 

az7000'

Veteran Member
Joined
Jul 7, 2014
Location
Flagstaff, AZ
TDI
2012 Jetta TDI (gone), 2014 Passat TDI (gone), 2014 Touareg TDI (Amazing!)

HerrK

New member
Joined
Dec 20, 2017
Location
Poway, CA
TDI
2014 Q5
Thanks for the input HerrK, Some on this thread get a little butt hurt and will call you names. PC means passenger car, I was unaware of that and was trying to help...
We love the Touareg just as much post fix! good luck
You know I am still confused regarding the way VAG/EPA classified our 2014 Q5 TDI as being equipped with the 3.0 TDI Gen 2 PC engine. I can only assume it was how VAG/EPA classified the original emissions test. So no hard feelings on my part from any flame throwers, as VAG's money spends the same no matter the title. Coming up on tank #1 mileage check.
 

KevinGary

Veteran Member
Joined
Dec 6, 2017
Location
Long Island
TDI
2015 A6 TDI
The PC engine designation is for the engine version with a torque rating of 428. The other versions of the engine have a torque rating of 406.
 

HerrK

New member
Joined
Dec 20, 2017
Location
Poway, CA
TDI
2014 Q5
You know I am still confused regarding the way VAG/EPA classified our 2014 Q5 TDI as being equipped with the 3.0 TDI Gen 2 PC engine. I can only assume it was how VAG/EPA classified the original emissions test. So no hard feelings on my part from any flame throwers, as VAG's money spends the same no matter the title. Coming up on tank #1 mileage check.
So about 2100 miles post TDI emissions repair and numerous tanks of fuel later. Just returned from a 800 mile road trip. Generally, across the entire full city to full highway, our milage is down about 4-5 mpg from pre TDI repair. So 24-24 city and 32-33 highway. I calculated the mpg by the manual miles/gallons. The on board milage computer is even more optomistic than before the repair. Not happy with the results, but still enjoy the Q5. It will be interesting to see other post repair milage results. C'est la vie.
 

Mythdoc

Veteran Member
Joined
Jan 28, 2017
Location
Tennessee
TDI
2011 Touareg, 2015 Q5, 2015 Golf
Not happy with the results, but still enjoy the Q5. It will be interesting to see other post repair milage results. C'est la vie.
I run with a Chipwerke piggy back tuner in. It helps with both powers and efficiency. I also run in manual mode quite a bit and am having luck retraining my transmission to shift at lower rpm’s when fully warm. I am seeing a small uptick in mpg in early spring. Two tanks and 1000 miles my average was 33.7, about .5 higher than pre-fix wintertime average. About 300 miles into this current tank, my on board computer reads 39.2, which normally translates to about 35 mpg.

It is obvious to me how much a Diesel engine likes to run in warmer temperatures. I can’t wait until summer diesel comes, which will be in just a couple weeks here.

Since I drive for efficiency, I would be very aware if the fix had greatly affected that aspect. It hasn’t. I won’t know hard numbers until summer, but it is looking very much like the mpg’s I get will not have deviated from prefix by more than half a mpg, if that much.

Why might others have seen a bigger drop off? The most likely cause would be a lot of cold engine operation. City driving, short haul trips, engine never fully warming. This keeps the engine in warm up mode when it is more affected by the fix programming. Interrupted regens.

Click my fuel link below and you can see my actual results. Final note: i live in a rural area. Few stop signs, fewer lights, lots of driving between 50 and 70 mph. Perfect for high mileage. That is why my numbers are very high comparatively.
 

HerrK

New member
Joined
Dec 20, 2017
Location
Poway, CA
TDI
2014 Q5
Just some history for the groups information. Our 2014 Q5 had 54,500 miles at the time of the repair. My wife has a 45 mile round trip commute daily. We live just outside of San Diego and sometimes she sits in a lot of stop and go traffic sometime she is moving at 75 mph. Not sure if we ever get winter diesel in southern CA.

Our recent 800 mile trip was to Prescott AZ via Phoenix. No real noticable changes in fuel mileage between CA or AZ diesel. I checked highway mileage multiple times on 120-250 miles stretches where there was less than 5 miles of accelerating/decelerating at fuel stops.

The financial cross over point is not worth it to me to invest in either the Chipwerke device or the VAG software to adjust the MMI readout so it is closer to actual manual milage calculations. The pre repair vehicle always exceeded the EPA specs of 24/31 (City/Highway) mileage. The post repair vehicle still exceeds the updated EPA figure of 23/30 mpg. FYI the government highway test is a 765 second run, 10.26 miles, with a 48.3 average mph. I have no complaints with the old vs updated government test data.

Prior to the repair we would achieve highway ratings similar to the excert from the article https://www.autotrader.com/car-news...-challenge-in-diesel-powered-audi-tdis-215208 below of 37-38 mpg highway. We are now at 33-34 mpg highway. Much like the article our recent average mph was 62-63 with the ac running. AZ speed limits are 65-75. CA is 65-70. I was running at the speed limits or 3-4 mph over. Similarly my wifes city go to work loop. Previously 26-27 & now 22-23.

38-mpg-rated 2014 A6 TDI achieves 43.6 mpg
38-mpg-rated 2014 A7 TDI achieves 42.7 mpg
31-mpg-rated 2014 Q5 TDI achieves 38.6 mpg

Dashing across the country in less than 48 hours is no small feat, but three new diesel-powered Audi models, driven by a group of eight automotive journalists, have conquered the challenge. Even more impressive than the quick times posted are the fuel economy figures the trio achieved. Each vehicle involved in the cross-country trek -- the 2014 Audi A6 TDI Quattro, 2014 Audi A7 TDI Quattro and 2014 Audi Q5 TDI -- beat its respective Environmental Protection Agency (EPA) economy rating by a significant margin.


Best of luck in your mileage data gathering. For us - it is what it is. We'll keep the vehicle until our next European Delivery in 2020. Hoping the German auto industry does a good job of integrating the battery and hybrid vehicles. Myself I'm thinking of one last potent ICE, sure not to be a diesel, prior to electricfication.
 
Joined
Sep 20, 2015
Location
Long Island, NY
TDI
Audi Q5 TDI 3.0L
No major complaints. Vehicle performs well post-fix.
Minor complaint is loss of city/local MPG. Average to date is 3 MPG less that pre-fix. Highway MPG is unchanged.
 

bbob

Member
Joined
Jun 4, 2018
Location
Northern California
TDI
2015 Audi Q5
Any recent observations of the 3.0 PC fix? I am still debating when I should get the fix done. Thanks
Don't do it if you don't have to. The car sounds like good ole diesel of 30 years ago, drives almost like one, and gets 4-5 MPG less than before the "repairs". And Audi considers that within "normal", despite promises of up to 1MPG drop and changes in sound and shift patterns that are noticeable during warm-up or high altitudes only. This is based on my 2015 Q5 repaired about a month ago.
 

KevinGary

Veteran Member
Joined
Dec 6, 2017
Location
Long Island
TDI
2015 A6 TDI
Don't do it if you don't have to. The car sounds like good ole diesel of 30 years ago, drives almost like one, and gets 4-5 MPG less than before the "repairs". And Audi considers that within "normal", despite promises of up to 1MPG drop and changes in sound and shift patterns that are noticeable during warm-up or high altitudes only. This is based on my 2015 Q5 repaired about a month ago.
That is what I have been reading. It is also what my service advisor is reporting about the fixes they performed. What engine do you have? How many miles?
 
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Dr Chill

Veteran Member
Joined
Dec 19, 2016
Location
South Florida
TDI
2016 A8L TDI
Just got car back from the 5000 mile service (performed at 6000 miles). 2.6 gallon of Adblue (DEF) consumption in 6000 miles. Car comes with a 6.2 gallon tank according to service tech.

Not bad, but this is a 2016 A8L which is supposed to have decreased DEF consumption after the emission compliant repair.
 

FixedTouareg

Member
Joined
Dec 29, 2017
Location
California
TDI
2015 Touareg
We like ours. Considering they gave as back almost $11k we like it even better. I already took 10k off sticker when I purchased it, so getting $60k suv for $39k isn’t that bad. The power is similar, mpg slightly down, and engine is louder, but it still is better than 100% of all cars that retail for $39k. It had a little more low end grunt, but it still is a strong engine.
 

bbob

Member
Joined
Jun 4, 2018
Location
Northern California
TDI
2015 Audi Q5
That is what I have been reading. It is also what my service advisor is reporting about the fixes they perf Reed. What engine do you have? How many miles?
Q5 3.0 TDI with about 36K miles. BTW, I disagree with some of the other posts about this being the best $39K car (taking into account payments I guess). What set the Q5 TDI apart was the combination of mpg and power that was unmatched. I don't have either anymore. Either my case is an aberration, or others are less critical of the changes after the "fix".
 

cmc

Veteran Member
Joined
May 9, 2002
Location
seattle, wa
I did the fix recently despite having a lot of info on what would happen to the vehicle. My main motivation was the 10 year warranty on all of the engine and emissions components. Sure the money was nice too, but I figure the free insurance on the guts was even more valuable.



So having done it is indeed a less pleasurable vehicle than before. I understand conceptually what has been done. Since the vehicle was emitting more NOx than it was supposed to, not only did they have to inject more DEF, they had to produce less of it in the first place by adjusting combustion parameters. And if you adjust the burn to produce less NOx, you end up producing more particulates. (more EGR, retarded injection timing, lower combustion temperatures)



So, less NOx means more particulates means more stress on the DPF (diesel particulate filter). To reduce the stress on the DPF, adjust the transmission to run it at higher rpms to produce a hotter exhaust, which will accomplish more passive regen.


It all makes sense to me what had just happened.


Here are some of the issues and how I cope with it:



Noisier note and turbo lag: This can be countered by using cetane boost to advance the timing as much as possible. Quite successful in this regard.


Transmission staying at lower gear: Nothing that I can come up with when it is cold. Perhaps somebody will figure out a VCDS coding some day. At highway speeds (i.e. 60-70 mph) I found that it did not want to shift into 8 and if you flip it to 8 it would want to shift back to 7. (see the reasons I theorized above). Therefore at highway speeds I have to go into M mode to keep it in 8th. Somewhat annoying but I can reclaim almost all of the highway mpgs prior to the fix.


For those of you guys seeing a big drop in mpg I was wondering if it was because of your vehicle staying out of 8th on the highway....
 

bbob

Member
Joined
Jun 4, 2018
Location
Northern California
TDI
2015 Audi Q5
Thanks for the info. I don't think I had paid close enough attention to see if it was stuck at 7 in highway driving. I will check that and let you know. That would be pretty lousy if it turns out to be the case.
 
Joined
Sep 20, 2015
Location
Long Island, NY
TDI
Audi Q5 TDI 3.0L
I have the gear displayed on my fixed TDI and it seems most of the time it is in 8th gear when going above 60. I'm going to try the cetene boost.

Which brand of cetene boost are you using?

Thanks.
 
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cmc

Veteran Member
Joined
May 9, 2002
Location
seattle, wa
Hi, I am using Power Service (the silver bottle). I keep adding until I get the smoothness and quietness that I remember the engine to be when I picked it up in Ingolstadt (with awesome Bavarian diesel). As for whether the transmission opts to shift into 8 or not I think that too is affected by DPF temperature. If you are hypermiling at 60-70 the engine could be so relaxed that the DPF falls below optimum temperature, hence the system orders more rpms...

I enable the oil temperature display to get an approximation of how hot everything is. I know that VCDS can access a ton of different temperature sensors in the system but that would be rather inconvenient to view and display while driving.
 

spratjack46

New member
Joined
Jun 20, 2018
Location
Texas
TDI
2014 A6
2014 A6 3.0 PC fixed late January 2018. A horror story, shifting has changed dramatically, 2000 rpm for lower gears until you hit 45 mph. I received document from VW stating my fuel economy would decrease 1 mpg. Currently 5 mpg less. Higher speeds, 70-90, there is a lag in response, not good in traffic. I filed a formal complaint with Audi and the guy said 'You're the first one we've had.' Gotta love that response. Texas has no emissions standards, should never had taken fix. Adios beautiful machine.
 

Mythdoc

Veteran Member
Joined
Jan 28, 2017
Location
Tennessee
TDI
2011 Touareg, 2015 Q5, 2015 Golf
Message deleted. Not worth the trouble I took to write it.
 
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cmc

Veteran Member
Joined
May 9, 2002
Location
seattle, wa
I just got back from a 1300 mile road trip to the oregon high desert. The Q5 was packed with stuff, had a powered cooler and did 2 climbs to 8000 foot elevations, one of which was unpaved. Overall it returned (a corrected) 34 mpg. It was also great having effortless passing power at high elevations.


I think I have gotten used to the lobotomized version of the car. Be sure to keep it in M8 on the highway and you will still see the impressive mpgs of the pre-lobotomized car.


I brought a bottle of DEF along just in case, never had to use it.
 

opsx

Well-known member
Joined
Mar 3, 2017
Location
Northeast
TDI
tdi
weird request: can someone with a fixed Touareg or Q7 post a picture of their emissions repair sticker? I think they place it on the underside of the hood and write in the date that it was done. Or do they put it somewhere else on the 3.0? Thanks!
 
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nobodyhome17

Member
Joined
Dec 22, 2016
Location
SC
TDI
2010 A3 2014 Q5
2014 Q5 post fix

Had fix and 95K service completed around the 94K mark. Noticed average loss of 1.5 to 2 in fuel economy.

Two weeks ago had steady engine light come on. Was told it appeared the engine caught a sweet spot in the regen coding and it didn't completes the cycle. Received Q5 back with the engine light off. The fuel economy for this tank was down 4-5 mpg from post fix averages.

Late last week, steady engine light returned and just dropped it off at the dealership and waiting on the diagnosis now.

In SC, has been in upper 90s with 100+ heat index the last couple of weeks. Normal commute is 70-80 daily (avearge 50/50 city/hwy) and average ~500 miles/week in the vehicle.
 

nobodyhome17

Member
Joined
Dec 22, 2016
Location
SC
TDI
2010 A3 2014 Q5
I was told the issue is a NOX sensor that is being ordered and hopefully available later this week.
 

bbob

Member
Joined
Jun 4, 2018
Location
Northern California
TDI
2015 Audi Q5
2014 A6 3.0 PC fixed late January 2018. A horror story, shifting has changed dramatically, 2000 rpm for lower gears until you hit 45 mph. I received document from VW stating my fuel economy would decrease 1 mpg. Currently 5 mpg less. Higher speeds, 70-90, there is a lag in response, not good in traffic. I filed a formal complaint with Audi and the guy said 'You're the first one we've had.' Gotta love that response. Texas has no emissions standards, should never had taken fix. Adios beautiful machine.
That's their standard answer (you are the first one to complain). I even pointed them to this forum and others online. Clearly you (or I) are not the first one to see the results and complain.
As I have pushed more with the local dealer and Audi, it is clear that what they (and their lawyers) are counting is that no angry customer can actually prove their MPG before the "fix". This is not speculation, it is what they came back with when I pushed them. "how are you going to prove what MPG you were getting before the fix?" Unless enough irate customers make a lot of noise, they are just going to pretend the problem and their deceptive statements many of us based our decisions on don't exist.
 
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