bpp

Me, 2014 Q5 TDI PP, 64,429 mi.
emissions compliant on Jan 11, 2018, 55,817 mi.
02 sensor faulty, replaced August 13, no charge warranty. 61,093 mi. (no CEL, complaint: occasional irregular acceleration with constant throttle input when cold)*
02 sensor faulty, replaced November 26, no charge warranty. 64,401 mi. (complaint: CEL, occasional irregular acceleration with constant throttle input when cold)
*Q5 in for regular service and the SA was advised of a driveability issue. GFF scan detected sensor problems FAULT P0133 SENSOR B1 S1 SLOW RESPONSE

gk1

Is it possible since the TDI fix/adjustment that it is eating up O2 sensors? Just a guess anyway.

bpp

No clue. We're still learning about the impact of the fix and maybe Audi too. I posted this because it is odd happening within a few thousand miles of last O2 fix. Maybe others will see it happen, both with and without a CEL and will have theirs checked after experiencing abnormal cold acceleration issues. .02

TomReed

I've had similar issues with an apparent change in power on my '14TDI when cold. Also had the glow plug light flash a frew times. Restarting the the engine made the light and power issues go away. ODB codes indicated low pressure from the tank pump. Changing to premium diesel appears to have resolved the issue.

MurrayA4

Yes this is kind of troubling.My 14 with 210k kms/ 130k mls.20k post fix has never consumed a Nox/O2 sensor.Many others have had a different experience.I'm a big believer in fuel quality.Fortunately I'm in Canada and our diesel standards are a little higher than the US.But I use one brand because they typically have a higher standard re Cetane and lubricity.So far so good !

bpp

Fuel quality may be an issue here. Never thought about it until mentioned here. Coincidentally, the fueling station I use changed over brands earlier this year. I'll use another source on next fuel up. Thanx.

MurrayA4

Yes if I was in the US I'd run Shell V-Power.From what little I know I have a sense that that's a good product among your choices.
There's a good VW Tdi site that speaks to fuel quality.The beauty of the Q5 Tdi is you've got a lot of range to find what you're looking for.
By the way rule #1 is always seek out a station that has a high turnover of diesel fuel.This stuff doesn't do well when it's sitting around underground for a long time, condensation and even fungus are can be an issue.

djgainsbond

I predominantly only use shell!! Followed by ExxonMobil, BP and lastly sunoco. I've used sunoco maybe twice In my 4 years of ownership, simply because it was on the highway. I've also not gotten the fix yet. I'm going to wait until the last minute. I've 98k miles on it.

bpp

I'm in eastern PA/western NJ and the stations providing diesel fuel do not adhere to the "branding" of their logo, i.e., Shell gas is Shell gas, but Shell diesel is sourced from somewhere else we know not where. The label on the pump (e.g.) tells you this is not a Shell product. Im not sure this is true everywhere. Wish we had a better alternative but it isn't so. Maybe others can add to this.

djgainsbond

yup saw that in passing. However, I'd think it'd be reputable if shell allowed it