Retuning for ULSD?

[TeDeEye1]

Since WV has to detune the TDI to meet our current emission standards do we get a retune when ULSD becomes the norm?

 

[svanmatr]

I asked the same question about a year ago. Nobody knows. Probably not in the works for a WV recall or warranty work. But I intend to make nice with the dealer just in case. I don't mind the crankcase ventilation being routed back to the intake manifold, but having that exhaust EGR going in there too is definitely not healthy. What that exhaust does, I don't know - yeah it raises the combustion temperature when the car is cold, but I think that might be to combat NOx emmisions, not sulfur.

So the question is "has the engine been detuned to handle high sulphur content?" or because of low cetane values found in North America.

If ULSD results in higher cetane values, then retuning is probably in order.

 

[dieseldorf]

retarded timing = reduced emissions

 

[Bob_Fout]

At the expense of what?

 

[dieseldorf]

reduced fuel economy
poor performance
rough running
hard starting
etc.

 

[Bob_Fout]

reduced fuel economy
poor performance
rough running
hard starting
etc.

So ULSD will be a good thing?

 

[eetsoot]

Kind of a good thing. We in Cal have had ulsd for a few years now. I find that with it you take a slight hit in economy, 2-3 mpg and a slight hit in power. Also the fuel foams up more so topping off your tank to the rim takes longer with it. These opinions are based on Arco (BP) diesel.

Other then those issues it's good stuff. I've always ran with the timing advanced. When I drive out of state, I don't notice anything that would make me want to retard my timing.

 

[dieseldorf]

I believe the ULSD will offer many benefits. First and foremost: far less soot/IM clogging.

Is VW gonna be able to re-program cars when USLD shows up? I kinda doubt it.

 

[TornadoRed]

We in Cal have had ulsd for a few years now. I find that with it you take a slight hit in economy, 2-3 mpg and a slight hit in power. Also the fuel foams up more so topping off your tank to the rim takes longer with it. These opinions are based on Arco (BP) diesel.

About 18 months ago I started a thread for discussion based on the hypothesis that Arco ULSD had a lower BTU content and cost TDI drivers 1-1.5 mpg. I was basing that on a series of 16 tankfuls, half Arco and half not, during the period from late March to early May 2004. (I should also note that I was getting poor fuel economy from all sources during that period.)

I've driven a lot of miles since then, nearly 100k miles. And because Arco has rarely had the best prices, I haven't used it very often. But when I have used it, my fuel economy did not vary by any measurable amount from the non-Arco fuels.

Since mid-October til about 2 weeks ago, I was using one independent station that had extremely attractive prices -- typically 30 cents/gallon less than major brand stations only a couple miles away, and lower than every other station in the county. Also, as other SoCal drivers may have noticed, this is the time of year when we see a major improvement in fuel mileage, with cooler temps and less AC usage. So I was very happy to pay less and get better fuel economy.

But I did notice a little sluggishness at one point (even with my normal dosage of Primrose), and needed fuel when an Arco station along I-5 was my best choice. And within a few minutes of driving I noticed that the sluggishness was gone. Also, I'm nearing the end of my 2nd tank of Arco, and I can tell that it has not resulted in lower fuel economy. So, I believe right now Arco customers are getting a high cetane fuel, with good BTU content, and at a competitive price.

Maybe Arco fuel was not as good during that earlier period. But there are variations between refineries, and variations between different batches from the same refinery. It's my opinion at this time, based on a lot more experience, that at least in SoCal there is no brand that is always the best or always the worst.

 

[windnsea00]

Our car has seen ULSD from Arco for ~85% of the past 20-25k miles. It feels to me it runs a tad smoother/quicker but more noticeably less sooty under hard throttle. It will still produce a decent puff under a quick full throttle hit but once it clears out after a few seconds it runs pretty clean, something that doesn't seem to happen with the normal diesel.

 

[mazot]

About 18 months ago I started a thread for discussion based on the hypothesis that Arco ULSD had a lower BTU content and cost TDI drivers 1-1.5 mpg. I was basing that on a series of 16 tankfuls, half Arco and half not, during the period from late March to early May 2004. (I should also note that I was getting poor fuel economy from all sources during that period.)
I've driven a lot of miles since then, nearly 100k miles. And because Arco has rarely had the best prices, I haven't used it very often. But when I have used it, my fuel economy did not vary by any measurable amount from the non-Arco fuels.
Since mid-October til about 2 weeks ago, I was using one independent station that had extremely attractive prices -- typically 30 cents/gallon less than major brand stations only a couple miles away, and lower than every other station in the county. Also, as other SoCal drivers may have noticed, this is the time of year when we see a major improvement in fuel mileage, with cooler temps and less AC usage. So I was very happy to pay less and get better fuel economy.
But I did notice a little sluggishness at one point (even with my normal dosage of Primrose), and needed fuel when an Arco station along I-5 was my best choice. And within a few minutes of driving I noticed that the sluggishness was gone. Also, I'm nearing the end of my 2nd tank of Arco, and I can tell that it has not resulted in lower fuel economy. So, I believe right now Arco customers are getting a high cetane fuel, with good BTU content, and at a competitive price.
Maybe Arco fuel was not as good during that earlier period. But there are variations between refineries, and variations between different batches from the same refinery. It's my opinion at this time, based on a lot more experience, that at least in SoCal there is no brand that is always the best or always the worst.

Tornado, do you add additives? I think additives may make the mileage/performance difference between ULSD and regular D#2 trivial. For example, my experience with BurkeOil ULSD is that it causes 2-3 mpg decrease in the mileage and slight improvement in performance (my car becomes more responsive with ULSD). I do not use any additives.

Mazot

 

[TornadoRed]

Tornado, do you add additives? I think additives may make the mileage/performance difference between ULSD and regular D#2 trivial.

I tried but failed to find the date I started using Primrose. I think it was around March 2004. I've added Primrose to every tank since then except biodiesel.

The additive may improve performance, just slightly. I use it mainly for lubricity and to keep the nozzles clean. It should have no effect on mileage.

 

[Bob_Fout]

My use of additives also didn't result in any MPG increase, but it did make the engine quieter and peppier. Less lag and faster revs.

 

[gtveloce]

Is all SoCal diesel ULSD now? Or just the ECD from Arco?

 

[eetsoot]

I've read that all Cal diesel is supposed to be low sulpher, less then 50ppm. ECD is less then 15ppm.

I will say that when I started using ECD was when it first started here in 2002, maybe there were some formulation changes. I stopped using it just because there wasn't and arco near me and that there were other cheaper stations. My car seems to like Rot gut diesel, everytime I buy fuel from out of state I do get an increase in mpg. I really don't care where I buy fuel from anymore unless it's off the beaten path and doesn't see much traffic.

 

[b4black]

The differences in fuel between LSD and ULSD will be small.

The difference between brand A and brand B is greater than brand A's current LSD and brand A's future ULSD.

 

[n1das]

ULSD can't come soon enough!

reduced fuel economy
poor performance
rough running
hard starting
etc.

Retarded timing also increases PM (soot) emissions. IOW, more smoke!

If I'm going to 'retune' my TDI at all, it's going to be for more power. I've already done that with Rocketchip Stage 3 tuning in my 02 Golf TDI.

I have my timing set at the top of the graph at the advanced edge of the spec, but still within spec. It runs real schweeeet at that setting. It'll be fine with ULSD, just cleaner.

ULSD can't come soon enough!

 

[imsos04]

Do you think ULSD will cost much more than "regular" diesel?

 

[gdr703]

I've read that all Cal diesel is supposed to be low sulpher, less then 50ppm. ECD is less then 15ppm.

From the Chevron website:
Most diesel fuel in California today is produced to a certified ALAD formula, with typical fuels having about 160 ppm sulfur, 21% aromatics, and a 53 cetane number.

 

[WisTDI]

Do you think ULSD will cost much more than "regular" diesel?

Here's some info on ULSD.

http://http://www.dieselforum.org/meet-clean-diesel/what-is-clean-diesel/new-technologies/ultra-low-sulfur-diesel/

 

[DavidG]

Here's some info on ULSD.

http://http://www.dieselforum.org/meet-clean-diesel/what-is-clean-diesel/new-technologies/ultra-low-sulfur-diesel/

Your link is broken, try this one.