ECO mpg

[DanHoug]

after my crank seal blew in my 91 Jetta NA, i got my parts car going and have been driving that... a 91 Jetta ECO. it came with good records and the previous owner logged fuel consumption over 150k miles and it always hovered around 39mpg. i've driven the car for one full tankful and got-- 39mpg.

my 91NA would routinely get 45 driving the same route at the same speeds. i thought the ECOs returned better mileage than the NA, especially given Hagar's experimentation.

anyone driving an ECO and what do you get for mpg?

-dan

[TylerDurden]

AIUI, the "ECO" was for eco-friendly, not economy. It had the catalytic and no aneroid.

That said, I would expect similar fuel-economy as an NA, if both are driven the same.

Hagar used the term "eco-mode" to refer to shunting the boost pressure away from his hacked aneroid feed-line, reducing enrichment .

[GolfGTD]

My son has a 91 ECO and his car always returns no less than 47 mpg and on long hauls he would get 52 mpg.

Nothing special has been done to it. Stock all the way around.

[82vdub]

Different trans gear ratios, tires, or ??

[DanHoug]

yeah, this has me kinda stumped... the car runs great, no smoke even with the Cat removed, starts fine. the timing might be slightly retarded as there is just a slight increase in knocking with the cold start pulled but the records show 39mpg thru a couple timing belt changes.

the ECO feels fast compared to my tired NA... really fast, to the point of suspecting over fueling. but i can't make it smoke black even floored (again, Cat is removed) so it doesn't seem over fueled. dunno.

-dan

[TylerDurden]

The turbo will provide more power than a NA, but it will use more fuel to get that pep. Drive it so it feels like the NA and see what numbers you get.

Get any grey/white smoke at high rpm?
I'm suspecting that these MK2s may often have injector lag at high rpms due to low IP internal pressure (or binding piston/roller-house), so I'd check that. The ECO tranny runs the rpms a bit higher due to the 4.11 R&P. A bit of advance might help, particularly if you do a lot of highway driving.