Newbie: Mk2 jetta action

[DEEPfrom1]

Hey everyone, I stumbled upon this forum last night. Very cool stuff here. My daily driver is a 1991 VW jetta 1.8 sohc 8valve 5speed. When I picked up the car in PA, I filled the tank and got 36 mpg while driving aggressively. Since then its been only NY gas which is 10% ethanol and my MPG sucks, normal driving nets me around 24-27 mpg. I know this car can do more! What kills me is this car HAS to warm up for at least 2 minutes before going anywhere or it won't drive (damn digifant).

Mods are:
- 2" drop (previous owner cut the springs) Will be getting coilovers in the spring
- Air box mod
-Digifast chip (supposedly helps with MPG)
-MEATY snow tires

The clutch slips if driven hard so I drive nicely! Anyone have any awesome tips or info for me about this particular vehicle?

-Mark

[gasstingy]

Hi Mark,

Welcome to the forum. I think you'll get your fuel economy up over time with some of the tips you find here. As for your Jetta, like ALL of our vehicles, adjusting the "nut behind the wheel" can have immediate positive {or negative in some cases} results. Hang in there. As for the previous mods on your car,

- 2" drop: probably helps since it reduces frontal area a bit (unless the lowered height makes it a snow plow in the winter )

- air box mod: if it is to bring in cold air for higher performance, it will hurt your economy more often than not. Not exactly intuitive for some of us who learned mods as related to going faster.

- chip: I'm not familiar with a chip for improved fuel economy, so I can't make a contribution here.

- meaty snow tires: probably hinder economy, but if they keep the car moving and not buried in a snowbank this winter.............

Again, welcome

Another Mark

[DEEPfrom1]

I will be replacing the intake with a stock unit and a K&N.

Chip: The chip makes the car run a bit leaner (they run real rich from the factory)


What are the thoughts on engine braking? Thats the key point to the digifast chip, normally the vw will eat a lot of fuel on down shifts/engine braking and this tunes the ecu not to send nearly any fuel while braking.

Just curious on the general census of engine braking and how it affects MPG.

Thanks everyone!

[gasstingy]

For my Kia Rio {1.6L / 5 Speed}, engine braking increases my consumption. I try to anticipate lights and traffic snarls, coasting out of gear when possible until I can resume my normal rate of speed.

One of the biggest personal changes I made was slowing down. I almost never exceed the posted speed limit unless I'm coasting down a hill. Then, I'll allow it to go over a small amount. Speed, anticipating traffic and gentle acceleration made a real noticeable improvement in my FE and reduced my wifes stress level at the same time.