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GS300 AWD six-speed auto transmission

The manual states that the car will not shift into 6th gear until the engine has warmed up. Don't understand why, but I can live with that. What I cannot live with is the following: Whenever you start the car cold and start driving, the transmission refuses to shift out of first gear unless you gun it enough (3000 RPM on the tach), then it behaves normally.

This occurs whether it is 100 degrees or below 0 outside. I frankly hate to gun a cold engine that hard if you do not have to. I asked my service manager if this might be a software problem, as it seems to be getting worse with time. His response was that the dealership could not do anything about the software of the transmission controller, but suggested I drive in S-mode, which disables the fuzzy logic used in the transmission, what Toyota calls "ECT-i the i stand for - with intelligence".

I did do that and from now on always drive in the S-mode, makes it easier to downshift, but the PROBLEM remains the same. Any thoughts out there?

Reply to
kitzler
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You are describing the normal operation of the electronically controlled automatic transmission. The system is designed to delay upshifts until the coolant temperature reaches a specific point so that the engine will run at higher RPM. By running at higher RPM, the engine will warm up more quickly. The faster the engine warms up, the faster it will enter closed loop mode for improved emissions, with side benefits of improved performance and fuel economy. As the ambient air temperature drops, it will take longer for the coolant to reach the target temperature.

Reply to
Ray O

Makes sense Ray but I still think it is wrong to run a cold engine at high RPM until it has had a chance to warm up.. If you say my transmission behaves normally, then so be it... thanks for the feedback.........

/Nick

Reply to
kitzler

I agree that running a cold engine at high RPM sounds counter-intuitive, however, Toyota has been doing this since they developed the electronically controlled transmission, IIRC around 1992 when it appeared in the first generation Camry.

Reply to
Ray O

I like the idea of running the engine faster to warm it up. But why does is take so long to get the car heaters working?

Reply to
mcbrue

Thanks Ray O, I can live with that and forgo all my engineering training, as far as McBrue, you ought to get heated seats, since I started using mine, I hardly need the car heater, keeping my butt warm in a car is like keeping a hat on your head outside, you don't need a coat..

/N.

Reply to
kitzler

Reply to
kitzler

Say Ray O., what about my comment on driving only in the S-mode which is supposed to disable the ECT-i (intelligence) from the tranny, I still get the same problem whether I use the D-mode or S-mode.......... Still I feel better driving after reading your comment, I really thought there was something wrong with my transmission and the dealer was just soft shoeing me.

/N.

Reply to
kitzler

While the engine is warming up, the air-fuel mixture has to be enriched for the engine to run, and while the extra fuel is being added to the mixture, fuel economy goes down and emissions go up. Also, the O2 sensors and catalytic converter(s) have to be fully warmed up to function, so the sooner everything gets up to operating temperature, the sooner emissions go down and fuel economy goes up and the easier it is to make the car comply with emissions standards. With this in mind, I think the designers would design the delayed shift parameters to override the D or S modes until everything is warmed up. As far as harm being done to the engine, modern motor oils do a much better job at temperature extremes and my guess is that there is little or no harm being done.

Reply to
Ray O

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