Turbodiesels At High Altitudes

listerone

Veteran Member
Joined
Jul 20, 2009
Location
Connecticut
TDI
2018 BMW 540d
We'll soon be leaving on a road trip to Colorado...west of Denver.There's a spot we intend to visit that's 14K feet above sea level and which isn't that far from Denver which,IIRC,is about 5K feet above sea level.I've never driven *any* car at anything *near* that altitude but I've read that while gas powered cars have trouble at such altitudes turbodiesels have little or no trouble.Can anyone who's either familiar with such driving or is a propulsion engineer confirm or refute my assumption? Any tips or warnings would also be appreciated.Just hoping to know what to expect.
 

jcrews

Top Post Dawg
Joined
Jul 28, 2007
Location
Round Rock, TX - VCDS
TDI
All gone
The ECM will automatically adjust to altitude, and the practical implications are nil. Even my 66+ kW VW had no problems at 5-1000 feet and I noticed a very slight drop in manifold pressure - less than 100 hPa at ~6000 feet. The MB will blast up the mountains with no problems at all.
 

No More Buffalo

Veteran Member
Joined
Mar 31, 2012
Location
Greenville, NC
TDI
Current: 2015 Golf SEL 6m Sold: 2012 Golf 2dr DSG
Not sure about the Benz, but on a CR VW, the turbo will "flat rate" the engine up to about 6000ft or so. In other words, you'll get full rated power up to 6k, after which it'll start to drop off like normal.

One thing to be aware of it that the increased boost used to make up power WILL raise EGT, so at altitude, while you don't need to baby it as such, don't hammer it either as while you'll have more power than you might expect, the engine will be working much harder than at sea level, or even at Denver altitudes, to produce a given amount of grunt.
 

ruking

Top Post Dawg
Joined
Mar 27, 2003
Location
San Jose area, CA
TDI
2003 VW Jetta, 5 M, Reflex Silver: 09 Jetta, 6 Sp DSG, Candy White: 12 VW Touareg, 8 Sp A/T, Flint Gray
We'll soon be leaving on a road trip to Colorado...west of Denver.There's a spot we intend to visit that's 14K feet above sea level and which isn't that far from Denver which,IIRC,is about 5K feet above sea level.I've never driven *any* car at anything *near* that altitude but I've read that while gas powered cars have trouble at such altitudes turbodiesels have little or no trouble.Can anyone who's either familiar with such driving or is a propulsion engineer confirm or refute my assumption? Any tips or warnings would also be appreciated.Just hoping to know what to expect.
Your MB E350 BlueTec should perform wonderfully from 5,280 to 14,000 + ft (Pikes Peak, I take it) There is of course a little fall off, but by in large the fall off is greater for normally aspirated and gasser engines. I even have notice fall off in a Corvette Z06, despite having GOBS of torque. All the best and have a wonderful trip. You probably already know this, but weather can literally change on a dime.
 

rotarykid

Top Post Dawg
Joined
Apr 27, 2003
Location
Piedmont of N.C. & the plains of Colorado
TDI
1997 Passat TDI White,99.5 Blue Jetta TDI
Not sure about the Benz, but on a CR VW, the turbo will "flat rate" the engine up to about 6000ft or so. In other words, you'll get full rated power up to 6k, after which it'll start to drop off like normal.

One thing to be aware of it that the increased boost used to make up power WILL raise EGT, so at altitude, while you don't need to baby it as such, don't hammer it either as while you'll have more power than you might expect, the engine will be working much harder than at sea level, or even at Denver altitudes, to produce a given amount of grunt.
I second all of that, Oil temps can skyrocket also shortening oil service life. The thing to remember about hard load driving is going up a mountain at speed produces a lot of heat so allow time for that heat to be disposed of......never just shut off an engine after a hard run.....
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Here's my story about 14,000 feet near Denver.........Pikes Peak!

Well, in 1982 I didn't think my Natually Aspirated 1.5 diesel Rabbit was going to make to the top of Pikes Peak..........then, I noticed a road grader moving along just fine near the top! After giving it some thought, I realized the Turbo made the difference!

As suggested, your TDI will do just fine!
 

Mike_Van

Veteran Member
Joined
May 15, 2003
Location
Boulder, Colorado
TDI
(SOLD) 2010 Golf, 2 door
I would expect your MB's auto transmission & ECU to do all the proper math for you, based on the O2 available at a given altitude.
The standard high-altitude + WOT @ low RPM warning is really only an issue with a manual gearbox. Yes, cooling the turbo @ idle for a few moments after a hard run is advised.
I don't know of any TD that tells the operator how hot the turbo is. Maybe they all should.
 

MonsterTDI09

TDIClub Enthusiast, Veteran Member
Joined
Jul 3, 2009
Location
NoVa/NJ
TDI
2010 Jetta DSG/ up keep on 2009 Jetta DSG 2006 Jetta Pag 2 in North SEA Green
Not sure if MB does this.On the CR the ECM will back off on the power if the ET get to high.Good luck have blast.

Tom
 

ruking

Top Post Dawg
Joined
Mar 27, 2003
Location
San Jose area, CA
TDI
2003 VW Jetta, 5 M, Reflex Silver: 09 Jetta, 6 Sp DSG, Candy White: 12 VW Touareg, 8 Sp A/T, Flint Gray
I would expect your MB's auto transmission & ECU to do all the proper math for you, based on the O2 available at a given altitude.
The standard high-altitude + WOT @ low RPM warning is really only an issue with a manual gearbox. Yes, cooling the turbo @ idle for a few moments after a hard run is advised.
I don't know of any TD that tells the operator how hot the turbo is. Maybe they all should.

I think you really make a key point and observation. The way the TDI, CDI's systems, and monitoring systems are designed or perhaps lack there of, really is gear to seamless and opaque operation behind the scenes, so to speak. For pete's sake, we don't even have oil temperature gauges !? What would it change even if we did? Another is even for folks that have gone to the trouble and expense of putting in oil temperature, turbo boost, manifold temperature, etc., gauges, it is like "so what"?
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
The temp of oil going to the engine should be very close to coolant temp...

Oil pressure is the missing item...not even reflected in ScanGauge!

There is a temp of IC exit air that's shown in ScanGauge ......... example: 105FiA

An exhaust gas temp (EGT) gauge with sensor probe located in the EGR manifold port will give you Turbo temp on that side..... maybe a similar device on the air pressure exit side would provide a contrast between the exit temp at the IC.....
 

dieselfuel

Veteran Member
Joined
Dec 28, 2008
Location
ohio
TDI
2003 Jetta TDI
I've been in those mountains mutiple times in my 03 TDI. No problems. A little noticable drop-off in power, but not problems.

Have fun!

df
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
You may notice more turbo lag - that's about it. Been a long time (11 years) since I've been at any sort of high altitude.
 

VWBeamer

Veteran Member
Joined
Jan 1, 2009
Location
GA
TDI
2004 Jetta Wagon
You'll pass all non turbo cars, regardless of there sea level rated HP.

I had a Dodge Daytona Turbo way back in 1986, and I passed everything going over the Rockies.

My Tdi does the same when I go in to the "small" mountains we have back east.
 

Rico567

Top Post Dawg
Joined
Jun 13, 2003
Location
Central IL
TDI
2013 Passat TDI SEL Premium (Turned in 7/7/18)
When we reflect on the role of a turbocharger joined to an engine, it's evident that moving to higher altitude is where any turbocharged vehicle will shine. It provides a greater air density in the F/A mix upon demand (in this case = higher altitude). So, up to a point (dictated by the capacity of the turbo) the engine output power can be maintained. Then it will drop off in a more or less linear fashion as air density decreases.
The real beauty of modern vehicles is the computerized control of all these factors, making for a much more driveable vehicle and pleasant experience generally.

Anecdote Alert!

We had the opposite experience in 1971 when we drove our 1967 Mercedes 250S sedan up in those mountains (got over 10K in the vicinity of Cripple Creek). Six cylinder with two Zenith carburetors, premium gas all the way. By the time we got to whatever pass it was, I was barely able to move uphill in the 3rd gear of a 4-speed. {Note: Yes, I know this situation could have been helped somewhat by changing the timing, but I didn't want to get into that.}
 

rotarykid

Top Post Dawg
Joined
Apr 27, 2003
Location
Piedmont of N.C. & the plains of Colorado
TDI
1997 Passat TDI White,99.5 Blue Jetta TDI
When we reflect on the role of a turbocharger joined to an engine, it's evident that moving to higher altitude is where any turbocharged vehicle will shine. It provides a greater air density in the F/A mix upon demand (in this case = higher altitude). So, up to a point (dictated by the capacity of the turbo) the engine output power can be maintained. Then it will drop off in a more or less linear fashion as air density decreases.
The real beauty of modern vehicles is the computerized control of all these factors, making for a much more drivable vehicle and pleasant experience generally.

Anecdote Alert!

We had the opposite experience in 1971 when we drove our 1967 Mercedes 250S sedan up in those mountains (got over 10K in the vicinity of Cripple Creek). Six cylinder with two Zenith carburetors, premium gas all the way. By the time we got to whatever pass it was, I was barely able to move uphill in the 3rd gear of a 4-speed. {Note: Yes, I know this situation could have been helped somewhat by changing the timing, but I didn't want to get into that.}
Could have been a flooded issue also, timing off and being over fueled because the jets are too big in the carburetor are a problem at higher altitude.... And you want lower octane not higher the higher up you go. We have 85, 87 & 89-91 for premium up here. Back then you could find 83 in the high country, the stuff would fix a carburated engine that was over jetted for altitude.
 

kpenner

Veteran Member
Joined
Nov 13, 2010
Location
Forney, Texas
TDI
2015 A6 TDI 3.0L
The last trip I made over the mountains I blew past everything on the road. Just a word of advice, they charge by the person to drive up Pikes Peak so be prepared to pay!!
 

Ace Deprave

Veteran Member
Joined
May 29, 2012
Location
Louisiana
TDI
Former owner of a 2012 Passat SE TDI (traded for a 2015 Golf R)
Yep, Mount Evans is actually higher, and less expensive. (The highest paved road in North America)
 

jrip

Veteran Member
Joined
Sep 17, 2005
Location
Fort Worth, TX
TDI
Jetta, 2000, Blue, TOTALED, Jetta, 2002, Green
Went to Colorado a few weeks ago. My 2000 TDI had no problems on Pikes Peak. I did have some loss of power going over one particular mountain but don't remember which one it was. Even there, nothing was passing me.
 

Silent_Kilt

Member
Joined
Nov 5, 2011
Location
Bakersfield, CA
TDI
'04 Jetta Wagon TDi GLS
I guess I don't even notice anymore. I live and work around 7100'. The TDI just always boogeys past just about anything I want it to.
 

16vjohn

Vendor , w/Business number
Joined
Jul 12, 2007
Location
Salt Lake City, UT
TDI
EA288 CVCA 6MT
I took the 98 Jetta up Pike's and to be honest, I noticed no power loss at all. Coasted all the way down and averaged 48 on that tank. That's a great drive, too bad I wasn't driving in the Pikes Peak Hill Climb.
 

gootie

Veteran Member
Joined
Jul 3, 2005
Location
Madison,WI
TDI
Golf,05,white TIP
mpuntain driving temps.

ScangaugeII usefulness
Trip from Madison,WI to Cedar City,UT via Denver is a great scenic route but when you are trying to do it without a sleepover things could get interesting. The Wife and I completed this trip in 27 hrs with a little route error on getting connection from I80 t0 I76.
I had no idea as to what to expect of the car with about 600# of gear and 2 people and driving at times 80-85mph.
Water temps on scangage got as high as 218 and tranny temp got to 234. Incoming air temps were as high as280. MPG for last 2 runs were 37.7 while I normally get 41-43 on my daily commute at 62mph in WI.
I also am down around a half liter of oil even though it was changed about 1000 miles before trip and I usually see no drop in 7500 miles of daily commute driving. I
I won't be in such a hurry to get back to WI as we are motelling 3 nights.
I will definitely change ATF upon returning.
Sure do love that RC1+ with boost gage and scan gage

I now understand that EGTs should have been monitored. I did not go into safemode once wheras down at WI conditions I can induce safemode with an attempt to get to 100mph asap.
 

16vjohn

Vendor , w/Business number
Joined
Jul 12, 2007
Location
Salt Lake City, UT
TDI
EA288 CVCA 6MT
Sorry to be off topic, but what in the world could have possibly been in Cedar City to merit that kind of trip? I mean... it's the desert... and not pretty cacti or anything... dry sage brush and flies.
 
Last edited:

arne487

Veteran Member
Joined
Jan 16, 2008
Location
Fort Collins, CO
TDI
'03 Golf TDI, '10 TDI Cup Jetta
We have our TDIs up that high frequently. No noticeable power loss thanks to the turbos, which means the slow drivers really get on your nerves.

The Audi on the other hand is slow at sea level, which makes it super slow at elevation. Even my sport bike seems like a slug at high elevation.

If you're looking for a good tour of 7 microbreweries within walking distance of downtown Fort Collins, look me up.
 

gootie

Veteran Member
Joined
Jul 3, 2005
Location
Madison,WI
TDI
Golf,05,white TIP
Sorry to be off topic, but what in the world could have possibly been in Cedar City to merit that kind of trip? I mean... it's the desert... and not pretty cacti or anything... dry sage brush and flies.
Daughter and hubbie with new GS. They are profs. at SUU-she in voice and he in physics. Yes it is beautiful there cacti and all. We stay at Crystal Inn cuz they have a bar!
 

dieselpower04

Veteran Member
Joined
Jun 26, 2007
Location
Outside Tampa, FL
TDI
2004 Golf GLS TDI (sold)
I climb Mountain Pass, CA everyday in my TDI and it takes it like a champ!

10-12 psi boost, passes all the vehicles like they were standing still :D
 
Top