New with a 2001 Jetta TDI
 

I have been working on this car for some time now, trying to improve my mileage. I hope to learn a few things around here and hopefully contribute somethings.

The car is listed in my sig and so are the mods. My next mod, hopefully by the end of next week, will be a 5spd swap.

Welcome to the forum! TDIs are great for fuel efficiency. If you do a lot of driving on the highway a "taller" top gear swap will help with MPGs.

Welcome to the forum!

Yep, taller 5th gear is in my plans as well...

I forgot to mention the 5spd I bought has the taller final gear so all of my gears will be longer.

Swap complete and the fuel mileage has improved but I have a bad Tstat and the car wont heat up to were it needs to be and so MPGs are suffering at the moment.

Get it fixed ASAP.

In varied driving, you should be pulling off 50+ mpg even without trying really hard.
Hypermiling, aim for 60 mpg.

Cool hand...I'm curious about your carbon fiber hood. I don't know if it would work on my '03 wagon (I see you've listed it for sale)...but how great is the weight reduction from steel to CF?...and of course, where did you buy yours?
Thanks!

I have the parts on order to fix the Tstat and a few other cooling system items which I want to change out just for preventive maintenance.

As for the Carbon hood it was already sold, shed about 10 pounds off the car from the metal hood, definitely not cost effective. And no measurable difference in MPG's.

The light weight rims on the other hand were good for about 2mpg's in the city. I will break even in about 2 years, I have had them for 4 years.

The 3 pedal mod is definitely cost effective, just in future maintenance it will almost pay for it self. Since I got it with the taller final drive it makes all the gears longer not just 5th.

With a bunch of friends, I once rented 2 vans, one of which had the Tstat malfunctioning, and it'd permanently run as if it was cold.
The difference is fuel use was huge.

You'd need to shed a lot more weight for it to show up in mixed driving.
But it can't hurt to do so ;)


If you ever need to swap the gearbox oil - you probably just did - VW apparently has some quality lightweight tranny oil that brings down fuel use as well.


Another fringe benefit, along with lightweight engine oil, but it seems to be helping me.

Yes I just filled the tranny with their synthetic light weight gear lube. Hopefully by next week I can do the Tstat and that will yeild some much better MPG's.