re. factory instrumentation accuracy & mpg
brett at cloud9.net
Sun Jan 26 13:10:56 EST 2003
At 12:24 PM -0500 1/26/03, ben swann wrote:
>Yes - peeve # 2 on the new aquisition of the '91 200 20v tq avant. Has
>SJM chip with 2.5 bar pressure transducer AFAIK. Gas mileage abysmal
>on the way home - 20MPG and no I was not easy on the gas and probably
>averageing over 70. My '87 5000 tq would get an easy 28 mpg under the
>same conditions. I thought Motronic was supposed to be superior at
>engine management, including economy, over CIS (CIS/motronic).
>What's up with that?
-wider(and different) tires
-several hundred pounds heavier
-flares probably don't help with airflow
-higher valvetrain resistance(probably negligible, but...)
-oil different viscosity, perhaps, that what you run?
-oh yes, and with the chip, did I mention "a lot more HP"?
Accelerating onto the highway full throttle can influence average
economy considerably if you have a chip.
Cruising on the empty highway, leaving it set on cruise control, on
the hakka Q's, I'll get about 24 tops at 75-80 indicated. My old
5000 would do about 2mpg more, usually, same speeds.
Off cruise control, traffic for passing? More like 22 or worse.
Keep in mind tires can play a factor here, and not just tire
pressure. The MXV4 "Energy" for example gets a few(very few) more
MPG than the regular MXV4. Let's also not forget elevations, wind...
"They that give up essential liberty to obtain temporary
safety deserve neither liberty nor safety." - Ben Franklin
More information about the 200q20v