audio_video_guy

I owned a golf TDI in the past and at that time there are a lot of discussions about HPFP and owners normally add additive to increase lubricity.

As I check this forum, doesn't look like it is a popular issue with Q5 TDI?
Any of you use additive at all? If yes, what frequency and what brand? Or is it good as is and we don't have to add any to fuel, just use top tier stations?

uberwgn

You won't find data on it like you do on the VW TDIs sold in the USA. There are so few diesel Audis in the USA. I've noted very few problems.

lja36

The lube I use is approx 2% to 3% biodiesel which is below the limit that audi allows and the min. needed for the lubrication properties to be effective. it is the most cost effective lube. If you go to tdiclub.com you'll find that the most likely reason for the HPFP problem is either contaminated fuel and/or fools pumping in gasoline. There is even an official gov. report on it... No further action to be taken by the gov.

djgainsbond

I've not added anything extra and primarily use shell. No issues thus far.

macwm

We are a family that has 2 Audi diesels, a '14 A6 3.0 TDI and a '14 Q5 3.0 TDI. We are thrilled with both, and I've often said that we will never purchase a gasoline vehicle again. This past winter was pretty frigid, with several nights below 0 (F) and finally on President's day the fuel in our A6 gelled, stranding me a mile from our home. After the temperature rose to a balmy 19 degrees (F) in the afternoon, I was able to restart and drive home. After speaking to our service adviser, I start to add the recommended amounts of Power Service Winterizer/Antigel (white bottle) to both vehicles. He had noticed a large number of calls all from TDI owner who had been fueling up in New Jersey that same day all with the same problems, with not ONE call from a PA fueled diesel. There were no further issues and in fact both cars ran smoother and felt as though they had more power.

The diesel sold in the US is generally 40 cetane, the bare minimum. In addition, you have no idea if it was winterized or not as apparently was the case with the NJ fuel. You would think that here in the Northeast that all diesel would be winterized, but apparently not. By the way up to the gelling incident I had used Shell diesel exclusively from stations in NJ. Now that spring is here (at least on the calendar) I've been using Power Service Diesel Kleen and Cetane Boost (silver bottle) with amazing results. Both vehicles feel as though they gained some power and just seem quicker. Also considering the fact that low-sulfur diesel has less lubricating properties, this is a no brainer. The Diesel Kleen claims to "clean dirty injectors, boosts power, improves fuel economy, prevents injector sticking, and contains slick diesel lubricator to protect pumps and injectors". You can buy it by the case on Amazon, and it costs about a $1.50 per tankful to enjoy a car that feels as though it had an API tune (I might be exaggerating a little).

Don Keener

How much do you add per tank? or per gallon?

audio_video_guy

I will do what I did with my golf TDI. I was using opti-lube XPD to prevent deposit, increase lubricity, water demusifier. It's also acting as de--icer and anti-gel.
If I remember correctly 1gallon last for a year or $45 at that time. I believe the website tell you rate of usage. So you just spend $50/year for peace of mind.

macwm

For maximum cetane boost add .64 ounces per gallon, for regular boost add half that or .32 oz per gallon (I go for the max). The bottles are marked so its pretty easy to figure out based on how much fuel you just added. You will also need a diesel fueling adapter to open the diesel misfueling protector (Audi part # 000-072-709)

MattMan3104

After reading other posts and there really being no negative comments from using an additive, I started adding Opti-Lub XPD to my Q5. For me it just seemed like there was a lot more to gain in engine and fuel system performance with little draw back. Having added it to the fuel now for about four months, I have not had any negative results.

Coolieman1220

Almost 5 years on my 335d and almost 5 years on the jetta tdi, never had a gelling issue with either. Last winter, my Q5 gelled in January. My guess was that many stations didn't switch over to winter diesel yet.

This year, I started using Powerserve winter mix. What a difference in all three vehicles. They start up super easy. Now I keep a bottle and add it when filling up.