mooretorque,

What else can you tell me about the temp sensor and the shift points? I've been studying this problem (for me at least) since last winter. Now that the colder weather is back, I'm doing a few more experiments.

From the manuals and wiring diagrams, there is one coolant temp sensor (variable resistance) that is used for engine and I think tranny shift control and 2 temp sensors (switches) used to control the coolant fans (radiator).

Therefore, my experiments deal with changing the resistance range of the first one I mentioned. I seem to have moved the shift points but not as much as I would suspect (experiments still in progress). The normal resistance vs. temp graph is in the manual so I have enough to work with. Just wondering if you or anyone else has dealt with this before?

The reason I consider this a problem is that when leaving work every night, I'm in a line of cars with fellow workers getting out of the parking lot. I have to pull out on a heavly traveled road that is doing 40- 45 MPH. You can see if I pull out and am doing 25 mph for the first mile (2+ min) I'm no longer the most popular kid on the block!

 

Hmmmmm..........don't really have anything to contribute to your analysis. I learned the reason when I took the car in after the first spell of cool weather the first year we had it.

But I agree that you should be able to affect the shift points by changing the range of the variable resistance temp sensor; alternatively, you could idle a little longer after startup. Except when not under load, it could take a while to warm up enough.

I'll ask the techs about it next time I take the GS in (since the 99 RX may be sold by then) and repost.

 

I've completed several more experiments and have so far concluded that altering the value of the coolant temp sensor will not change the shift point. As a negative side effect, the engine suffers starting problems if the ECM is tricked into thinking the engine is warm (lower resistance from the sensor). I'm thinking the O2 level is also a contributing factor to holdiong the tranny from shifting.

I've kind or wrapped this investigation up for the time being and will have to revert to plan "B". That is, as suggested by mooretorque, get my type A "I have things to do" New York minute attitude under control and sit in the vehicle letting it warm up !

 

I think I might be jumping into this thread halfway in, since I see the first post contains a quote, but don't see the original message, so if this has been discussed, sorry.

I don't know if this would be a practical workaround for you guys, based on where you park your vehicles, but have you considered installing a remote start on your vehicles? I realize this wouldn't truly fix the problem, but especially in ederny's case, where it seems as if this is almost a safety issue, it might be worth it. Of course, the practicality of this option would depend on whether or not your vehicle would be "in range" of the remote start transponder when you needed to use it. We have remote starts on two of our vehicles, and I assure you they're used on both the cold days (leave the heater on max when you exit the vehicle) and the hottest days (leave the A/C on max) as well. This is also helpful on days when there is ice or snow on the windshield, as you can let the car run with the heat coming out of the top vents and it will melt most of whatever's on the windshield. You can start your car in your robe and fuzzy slippers while sipping coffee, get into a nice toasty car, and not have to do much scraping to clean off your windshield and drive off knowing your cars will shift properly.

 

cms,

Thanks for the idea of remote start. That would really help and when leaving work, I can start the vehicle from the third floor - the RX is in sight from my office and the remote entry works from up there.

Can you tell us which remote start you use, where to get it, and who installed it?

 

ederny --

I will try to get the info for you. My husband has it on two of his vehicles, his personal truck and his work van. Since our garage is the realm of my RX330, his vehicles sit outside, so they both have the remote start. In his words, "I'd never own a vehicle without a remote start again". We didn't go through an audio store, as we have a friend who does car electronics installation on the side, so he supplied everything.

I'll try to get the info for you and post here.

 

ederny --

The brand of remote start my husband has on both his vehicles is Python.

A couple of things to be aware of, however:

1. Both vehicles have combination alarm/remote start units. Both transponders have lock/unlock or arm/disarm and "panic" buttons on them (neither vehicle came with a stock alarm), and the vehicle is started by pressing two of the 4 buttons together. I don't know whether Python makes stand-alone remote start units or, if they only make combination units, you might be able to simply not hook up the alarm part.

2. If you look at other brands, the primary thing you want to look for is the range of the transponder. We originally had an Alpine alarm/remote start unit installed in my husband's truck, but the range of the transponder was so poor that he had trouble starting the truck when it was only about 30 or so feet away, and he got rid of it. The range on the Python is very good.

In any case, a couple of other things I can tell you about his particular unit are that if the vehicle fails to start the first time, the unit waits about 3-5 seconds and then re-tries. His truck has never failed to start after the 2nd time, so I don't know what the unit's maximum attempts are. Also, the truck will shut off automatically after 20 minutes. I would also assume (but I'm not sure) that there would be away to shut off the truck remotely by pressing some other combination of buttons on the transponder, and you can also turn off the vehicle from inside by pressing the brake pedal.

Anyway, I hope all of this is helpful to you.

cmstahl