3.1 - Transmission Oil

[kingarthur2]

As the temperature in the UK drops close to freezing, my Transport 3.1 is out of the starting blocks like lighting. Is this due to the transmission oil being cold and, if so, is it possible to use a thicker transmission oil in the summer months.

[GTP Dad]

Colder oil will produce more friction and slightly better performance. Unfortunately, transmission fluid only comes in one viscosity for automatics. You could try a tranny cooler to keep the temps down as that will do almost the same thing.

[LMP]

King, I think it has to do with the mixture vs temperature curve imbedded in the computer. I have noticed with mine that cold temperature makes the computer deliver more fuel..much more fuel ..and inversely, warm temperature in a way starve the engine. IN a way, the curve is not a perfect match. In fact, the enrichment with cold temperature is so large that it induces what I consider catastrophic fuel mileage to the point I have installed a resistor to bypass the temp sensor to fool the computer and make it think temp is warmer and I get much better mileage.
If you like the boost, I think you will disregard the fuel consumption.

[guido0136]

LMP - Are you able to post a picture or details of this? Anyway I can save on fuel is great.

Thanks.

[LMP]

www.avigex.ca/xport/enginesensors.jpg
The mod is on the right side of graphic. One side is spliced to yellow wire, in my case near large C111 connector near firewall passenger side, to other side to any common ground. I ran both wires in through firewall and installed the switch under dash.
It makes a large difference at very low temperatures to the point the engine will not fire up if you forget the switch in "fool" mode. But as soon as engine has revved for some time..say 1 or 2 minutes at very low temp, less at more clement temperatures, switch the switch to ON and you will not see any difference in performance..a small dip at throttle up --mean, pedal down - if you have switched in too soon..and the unburnt fuel smell goes away...and engine warms up faster...yes..! For the record, rich fuel mixture is used to help cool engines in air cooled aircraft engines, during climb at full power..the unburnt fuel takes away heat by evaporation...As we lean the mixture, the exhaust temperature gauge goes up.
THe mod has very small effect in summer driving cause the engine will reach "closed loop" mode much faster. THe mod modifies mainly the "open loop" calculation , but this mode lasts much longer in winter as engine is slower to warm up.
IN cold winter driving,that is short city runs, increase in mileage is VERY noticeable... in fact this was the primary reason I investigated the possibilities: my first mileage measurements (bought the car end of December '93, just cold city driving) had just stunned me (once engine was warmed up, like highway driving I did later, mileage is just OK...so I thought the difference between cold runs and warmed up runs was just too large).

[guido0136]

LMP: I not up on reading schedmatics, but if I understand correctly I need a "2.2K resistor"??? ALso, what is a C111 connector? Are you able to post a pic???

Thanks.