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I took delivery of my 2010 Golf Wagon TDI (Jetta Sportwagen in the U.S.) about three weeks ago. So far it has exceeded my expectations. My fuel economy continues to improve as I put more mileage on it.

My car is a bone-stock Comfortline with no options. It has the cold weather package that may be an option in the U.S. but that’s standard here in Canada.

I traded in a 2006 Mazda 3 GT Sedan with the 2.3l engine. I loved that car but the fuel economy was surprisingly bad. My wife owns an 06 3 GS Touring Sedan with the 2.0l engine and her fuel economy is far better than what I was getting. That’s no longer an issue since I bought the Golf TDI.

This isn’t my first diesel car. I had a 2005 Jetta Turbo Diesel that I bought off a lease in 1997. 2005 was the last year for that particular engine as the following year they brought out the TDI. My ’95 had all of 75hp and I recall that passing on the highway in the summer required turning off the air conditioning in some cases.

I have a couple of questions specifically related to the manual transmission that I’m hoping that someone might have some insight into.

The first thing is stalling it. I remember that it was impossible to stall my ’95 because of the torque it had. You could put it in first and dump the clutch and the car would slowly chug away. Not so with my 2010. I’ve driven a manual transmission for most of my driving life and traded in a manual for this car. On the first day I had it I stalled it twice. That’s happened a couple of times since too. My wife, who also only drives a manual, has also stalled it several times. Apart from getting used to the clutch, it seems to me that with 236 lb-ft of torque that stalling this car should be impossible. I’ve not seen a graph of the torque curve, but is it really light on torque right off idle? It seems odd that it should stall. Any thoughts? My other theory is that maybe with 236 lb-ft or torque there is some automatic protection built in for the clutch. That amount of torque in a small car is unheard of in the North American market. Is this possible?

The other question deals with gear ratios. My ’95 was a manual and I don’t remember it being any different from any other car I drove with a 5 speed manual. However, with my new Golf it seems that the combination of the TDI engine and six gears makes for a remarkably different way of driving. In my Mazda I could drive 60kph (35mph) in fourth gear no problem. In the TDI, fourth gear puts the engine at just 1500-1600 rpm. This seems low, but then again with the diesel trend of an early and deep torque curve this probably isn’t an issue. I find instinctively that I reach for a downshift on slight hills, though the car will chug along nicely at 1600 rpm. Should I just get used to seeing lower rpms on the tach or should I use a lower gear? (Third would give rpms of closer to 2000)

Finally, on the highway at 110kph (65mph) in sixth gear I’m only at 1700 to 1800 rpm. I use the cruise control and there doesn’t appear to be a problem. One route I drive has some serious hills and it’ll hold sixth with no problem. I suspect it’s that fat torque curve again. But if I were to try to get the best possible mileage, I presume that I’d have to drive 90kph (55mph) in sixth, which would probably have the engine turning over at 1400-1500 rpm. Is this reasonable? Has VW built the engine to perform like this?

I’ve been following the good recommendations on the break-in period, but I’m wondering how I should look to get the best mileage from this car once it is broken in. Once the engine is broken in, should I just go with the highest gear reasonably usable and not worry about the low rpm?

(The flip-side to the low rpm thing is that I quickly learned that I MUST use cruise control on the highway. The car is so quiet and the engine turning over so slowly that 2000 rpm on the tach in sixth gear has you at a speed that will attract some attention from the cops.)

Any advice will be appreciated

Thanks
Mike
 

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Mike - First off. OMG! you need a little lesson on brevity. Your post intimidated me at first. ;)

The issue with stalling this car with a manual transmission is very common. In fact, the first time I drove one the salesman said "I guarantee you will stall it, as everyone does." To this day, I have not come close, but I have a high degree of driving experience and training. Anyway, you seem to have the issue of torque reversed a bit. It is because of the engine's torque that you are stalling the car. The lower the torque, the less likely that you will stall an engine. Maybe think of a Geo Metro with a manual trany versus a giant dump truck. The Geo is way low on torque, making the car very easy to drive by the least experienced of drivers. The dump truck on the other hand is made for pulling power and if one has never driven one, you'd be guaranteed to stall it...probably many times because of it's torque.

I think the key to getting the very best gas mileage is to keep the RPM's to the lowest that you can without bogging down the engine. This is why the DSG is giving the same car better mileage, apparently, then the manual. The DSG is designed to be constantly shifting up and down while trying to keep the minimum RPM needed for what is needed of the car at the time. A lot of people drive manual transmissions "high revving" to give them the most control over the accelerator, and in doing so will certainly suck more fuel, but the DSG is maintaining the lowest RPM needed for the engine and thus giving it the most economy...so long as you are not in the "sport" mode or manual mode.

I hope that his has helped a little in answering your question.
 

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This isn’t my first diesel car. I had a 2005 Jetta Turbo Diesel that I bought off a lease in 1997. 2005 was the last year for that particular engine as the following year they brought out the TDI. My ’95 had all of 75hp and I recall that passing on the highway in the summer required turning off the air conditioning in some cases.
I assume you mean a 1995 not a 2005.

Yes, you're upshifting at too slow a speed and too low an rpm. Keeping the engine low is fine on a level road and the engine has enough torque to do it. Don't be afraid of higher rpm. It's better for the turbo and oiling. IMHO, around 1800-2200 is best for normal driving. 1500 is low for going up hills.

For max mpg, the highest gear you can use without lugging the engine is best. This means that going up hills you still want to downshift or carry enough speed and momentum that you don't have to downshift. Going down hills you can upshift and coast. I've found that what makes a bigger difference is how you accelerate and the speed that you drive. Fast acceleration = wasted mpg. Drag is about the square of speed so there's a big difference in economy going 60mph vs. 75 mph.

When on the highway, use visual clues, scan the instruments, note relative motion to other cars, and feel the tire/wind noise and you'll get used to the lack of noise.
 

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Fast acceleration = wasted mpg.
I've frequently heard (and followed) a different opinion about accelerating economically, such as: "All engines are most fuel efficient when running near wide open, at low RPMs. If you have a manual transmission you should accelerate hard, but shift at low RPMs (generally around 2300, but this varies from engine to engine). Owners of automatic transmissions can’t do this, they have to stick with slow accelerations."
 

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I've frequently heard (and followed) a different opinion about accelerating economically, such as: "All engines are most fuel efficient when running near wide open, at low RPMs. If you have a manual transmission you should accelerate hard, but shift at low RPMs (generally around 2300, but this varies from engine to engine). Owners of automatic transmissions can’t do this, they have to stick with slow accelerations."
Does it make a difference that on gasoline engines they use closed throttles which cause a vacuum?
 

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Stalled at first too

When I first drove my new Golf TDI out of the dealership three weeks ago I stalled too, and did so a couple of times the first few days. I owed this to the vast difference between the tight new Golf clutch and the loose 10 year old Dodge Dakota V6-5 speed I had been driving. Especially since when I drove the Dakota the other day for the first time in three weeks I stalled that! None-the-Less, the YouTube review by Consumers Reports on the Golf TDI mentions that "it's easy to stall" so there may be something to that.
 

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I've stalled it a couple of times too-thought it was me- its embarrasking. :)
 

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It's good to see someone else posted this thread... I was seriously thinking about asking for myself.

My first manual was a 2003 VW Jetta GLI VR6 Sedan with 6 gears. I loved it! Especially the 6th gear on long drives. My subsequent cars have all been 5-speed manuals. The first 5-speed... I bucked that car for a good few months. It is QUITE an adjustment switching between the two if you haven't done it before, with the different gear ratios. Don't feel bad! After you get used to that 6th gear... you won't have any issues going between 5 or 6 gears. At least, that's my experience.

I was wondering about stalling with TDI's, since it happens even to the best of us. Being that I've only driven TDI's on the lot, back in the days when I sold VW's.

Does it start right backup (quickly) like a regular gas engine? As opposed to sitting and waiting for the glow plugs to warm up enough? Or does that really depend on how "cold" the engine is?

I'm still trying to decide on a newer TDI or an older used one... versus driving my Subaru into the ground in the next several years. I know its engine won't last nearly as long as a TDI. So, that's why I'm asking these questions.... knowledge.
 

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Starts right up. No waiting at all- ever.
 
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