Tow-rig. Ooops, Touareg, the diesel hauler

In reply to Parker with too many Projects :

I usually fill up when the low fuel light pops on, or just before it.  The tank is 26.7 gallons and I usually have about 5 gallons left when I fill up and have done 515 (ish) miles.  So that's around 625 miles to dead empty.  I think the people claiming 700+ on a tank are emissions deleted, which makes a big difference in mpg, and/or do a lot more freeway driving than me.  With the tune I was getting around 24 mpg mixed, this tank untuned I suspect it'll be close to 25 mpg.  My wife, who has a longer freeway commute than me, plus drives under the speed limit on the freeway (like 50mph vs me doing 80 mph), averages 27mpg in her untuned Cayenne diesel.

I'd recommend the Malone tune vs the Darkside one.  Malone has great support and also has TCU tunes, including the free pre diesel gate tune.  I've been happy with them so far.

I'm getting 23 in terrible stop and go traffic with the Malone Stage 2.5 and Nur-Spec TCU tune. The power is impressive but it is a little twitchy at slight throttle inputs which makes it tricky to drive smoothly. I may go back to the Stage 2 tune. 

Just an FYI. The CP4 fuel pumps are fuel lubricated and cooled. They are subject to catastrophic and expensive failures caused by trash, fuel starvation, overheating, and such. The failure sends shrapnel throughout the fuel system requiring the replacement of the pump, injectors, tank, and pretty much the rest of the system. 

I have read some suggestions to not run CP4 vehicles below 1/4 tank of fuel to make sure there is enough volume to keep the pump cool.

Religious fuel filter changes will also help the lift pump keep the HPFP supplied. 

I have also read that pump failure rates are 1% in Europe compared to 7% in the US due to the lower sulfur and lubricity requirements for US fuels. The US has a Wear Scar Diameter spec of 520-microns compared to the 460-micron spec in Europe.

I have only been buying major brand fuels and I have been running Stanadyne Lubricity Formula every couple of tanks to add some lubrication back to the fuel. It may not help but I really don't want to be in the 7%. 

In reply to Toyman! :

I mean, sure, more fuel is better.  However my wife certainly doesn't do that and we've put 100k miles on her cayenne without a problem.  That doesn't mean we won't have one and it'll mechanically total the car, but I wouldn't say the 1/4 tank thing is a must do.  I do regularly change the fuel filters, so we've got that going for us.

Filled up today, 24.3mpg on this tank, basically the same as usual.  So I'm going to reflash the Stage 2 tune tonight and call it good.

Dang, mine has never gotten higher than 22mpg on the tune/DPF delete, mixed with 60% highway, and I'm babying it because I don't want to blow soot. Stock I could regularly get over 25. Injector set points and balance look good, so I'll look to Malone as a possible solution.

Flashed the tune back on after work yesterday.  Definitely a large difference in HP/torque, makes the car much more pleasant to drive and matches the Malone pre diesel gate transmission tune better too.

Cabin air filter installed.  Thought I'd ordered tpms for my winter wheels but turns out my FCP Euro order got all screwed up.  Top tip!  Don't have multiple windows to FCP open, the cart doesn't update from window to window.  So I had to return some parts that somehow I ordered instead of the ones I needed, then reorder the stuff I needed.  Need to do an oil change on this, then have the tpms installed in my winter wheels and swap those on and clean out the cowl drains at the same time.  Then it's ready to go.

So I've been curious what the real life differences between the Malone Stage 1 and Stage 2 tunes are.  Especially given that their HP and torque ratings are basically the same.

Malone recommends Stage 1 for towing, due to lower egt's.  Given that when I drive up to Vail in the winter I'm in boost almost the entire time I figured lower egt's would be a good thing.

So this past Thursday I flashed Stage 1 onto the car.  Been driving a bunch this weekend and while their hp/torque ratings might be the same, the driving experience couldn't be more different.

Stage 1 feels like stock, but with more power.  Smooth onset of power, linear throughout the rev range and gas pedal position.

Stage 2 has much more power under the curve and the car is markedly quicker than Stage 1

I'm undecided if I'll leave Stage 1 on, it's probably a good idea for the ski season at least...

For a little more info, the Malone Stage 2.5 tune is twitchy. Tip in on the throttle is abrupt and difficult to do gently. It makes driving in traffic difficult at best. The power is off the hook but it's like a horse that is a lot too spirited. It always wants to GO. 

That said, with the delete and reasonably easy driving, I'm getting 23 mpg around town in traffic and 34 mpg on the highway. I will probably be going back to the Stage 2 tune. 

Where I live they do emissions testing every other year, which includes a visual check that everything is there.

so can't do a delete

Welp, that's what I get for wandering into THIS thread. Now I want a Cayenne diesel. And they're *relatively* cheap. 

In reply to Mndsm :

I've got one of those too.  It's definitely a lot nicer inside compared to the touareg, but for whatever reason, the tourareg shifts better.  I like the cleaner, simplier layout of the interior more too

In reply to docwyte :

Yeah, that's why I started searching cayennes. I was reading this thread because the diesel toureg always intrigued me and then I saw you mention diesel cayenne. I know of the cayenne and it's legendary depreciation status - means I can get a whole lot of really awesome truck for not a ton of scratch. And of course nothing says reliability like 10-15 year old uber-german. 

In reply to Mndsm :

Hmm, well right before my wife's cayenne went out of warranty the dealer replaced the DEF injector, catalytic convertor and both NOx sensors.  Probably $6000+ worth of work, so very happy it was still under warranty, by ~1200 miles!  Yeah, I could've bought delete pipes and a tune for it but then I'd have to register it in Montana and in general, I prefer to not remove emissions stuff.  Even with the pipes/tune that'd be ~$2000.

So I guess, just like buying any older, used German car, be prepared to spend a bunch of money out of warranty here and there...

In reply to docwyte :

Florida, baby....what rules? 

But this would purely be a backup vehicle for no real reason. Primary is VERY likely to be a Lexus NX hybrid in the next year or so. 

In reply to Mndsm :

That does open up options, although I still shy away from removing emissions equipment.  If the DPF or Cat go bad in either of ours in the near future I'm not sure what I'd do tho, as they're both good vehicles...

In other news, a 2015 E63 AMG S wagon popped up locally for sale.  Umph, I've always wanted one of those, I'd prefer a 2018 with the newer motor but a 2015 is more attractive price wise.  Of course it's still ~4 times more than what I'd probably be able to sell the Touareg for, so I'll likely just gaze at the ad longingly and that's it...

Oil change done today.  Bought the oil change kit from FCP Euro, opened it up and found they'd sent 3 different kinds of oil, all different weights.  Thankfully the big bottle was what I needed and I had enough matching stuff here to do the oil change.  Called them up, they're going to send me 4 more quarts of the proper stuff...