tcfitzpa

Hey crew,
I am a first time writer on the site but I have been using it for years - can't thank you all enough for the wisdom, help, and guidance!

I own a 2001 RX300 and just had the transmission totally rebuilt (oh the joys of the 1st gen RX's). But here's the thing - the car is shifting pretty hard between 2nd-3rd gear. It does it about 50% of the time and only between those gears. The mechanic said I need to give it about 1000 miles to "reconfigure" itself and learn my driving patterns. Is that true?

I am selling the vehicle and want to ensure that the car is running smoothly. I have been tempted to send the ECU to a repair shop (I found a few online sites that swear this is the answer) and see if that is in fact the problem. Anyone ever do that?

Or, should I just take it to the dealer to run some diagnostics?

I am totally at a loss and would love some advice. Thanks!

tcfitzpa

Sorry, mean ECU & EMC!

sktn77a

iTrader: (2)

I don't believe the first gen RX used adaptive transmission logic. I doubt very much that this will go away.

hypervish

It does in fact have adaptive logic.

hypervish

OP, sounds like you need to reset the ECM using Toyota Techstream. There is an option in there for resetting the ECM after transmission replacement/rebuild.

See how much the dealer wants to charge for that, or else you can buy a non-genuine Toyota Techstream cable on Amazon for around $25-30 with software and do it yourself.

Doing it via the techstream software is not the same as unplugging the battery cables for 15 minutes. That only resets driving habits, whilst this will reset everything regarding the transmission.

tcfitzpa

hypervish,
Thanks for the info - I had already tried the whole "unplug the battery/fuses" a few times with no luck. Good to hear that there is another layer/level to resetting the ECM.

Is doing it myself something relatively easy to do?

Can't thank you all enough!

tcfitzpa

Dealer just said price starts at $135.

Looks like if I do it myself, I hook the tech stream to a laptop--and then? Is there just an option for resetting the ECM?

sktn77a

iTrader: (2)

I guess it depends on how you define adaptive logic. The RX300 will change shift characteristics for things like outdoor temperature, etc, but does it adapt to the drivers driving characteristics (like the more recent cars - my LS460, for example)?

I still doubt very much that anything will change - I suspect the rebuild here.

hypervish

Yes, it absolutely does change depending on the drivers habits. This is nothing new, my 1996 Dodge Grand Caravan had it too. You will find Lexmex's posts on this here as well. Or you experiment yourself, drive the RX hard for a week and then very gingerly for a week. There's a very clear difference in shift logic.

hypervish

Yeah, it's very simple. "Hardest" part will be getting the software installed, I can't share any details here as it's not necessarily legal; however a quick google search will reveal many details.

Once you have the tech stream installed, plug in the USB end to your laptop and the other end to the OBDII port near the parking brake. Simply launch the program and enter vehicle info. You will be presented with various menus, under one of them you will find the option to reset the ECM. I can't remember the exact terminology, but it's there for sure.

I actually ran that reset for another RX300 owner that I know once they had their transmission replaced. It cured the problem for them, but for them it was a 3 to 4th shift issue. It doesn't hurt to try it on your RX, worst case it doesn't fix it; and there is an actual mechanical issue with your rebuild.

tcfitzpa

Do you think this one will work? It seems like the best option on Amazon.

Fotga Newest V8.00.034 MINI VCI for TOYOTA TIS Techstream Diagnostic Cable & Software Model: ZB031 Car/Vehicle Accessories/Parts

tcfitzpa

hypervish,
Do you think this one will work--it looks like the best option on Amazon -

Fotga Newest V8.00.034 MINI VCI for TOYOTA TIS Techstream Diagnostic Cable & Software Model: ZB031 Car/Vehicle Accessories/Parts

hypervish

Yes, that should work. It's the same version that I have.