[fenixus]

haven't found any yet.

I changed thermostat which made the car warm up quicker in cold, I flushed the ATF a few times, changed strainer, adjusted the kick down cable. all of it helped a bit each, but nothing really solves it when ambient temps are around 30F (or lower).

other idea, is to simply wait with car idling for 2 minutes in parking lot (in Winter I mean) to make it warm up a bit before you drive away. the problem is minimal then (if any).

This has never been a problem in the past though. What is the 'solution' to the 'problem'?

 

[JohnGD]

hmm, I thought when the coolant is cold the ECU stops shifting into OD. Didn't realize ECU stops going into 3rd.

Maybe inspect the engine coolant temperature sensor too? At least check the readings when cold.

 

[CarryMeBF]

hmm, I thought when the coolant is cold the ECU stops shifting into OD. Didn't realize ECU stops going into 3rd.

Maybe inspect the engine coolant temperature sensor too? At least check the readings when cold.

Well, when i finally flush my radiator I am planning on changing it so...that would take care of any problem with that...

Any help with what I asked below, John?

Going back to the DIY instructions here: http://www.toyotanation.com/forum/10...procedure.html

I have a different transmission. So I assume the capacity is going to be different. If he is using 10 liters to flush his transmission what would I be using? in a V6 A541E Transmission?

 

[fenixus]

I don't kow technical details on ECU programming, but it all works normally in Summer or when warmed up a bit in Winter. i assume this is how they programmed the ECU. perhaps I'm wrong and some part somewhere is not working right. I don't even know what else to check...

I have a brand new OEM ECT for EFI sensor (old one had a dead spot around 50F) and it didn't change much.

wondering what else could be affecting it, if this is not how it was designed?

also, even when car is dead cold, it actually will shift into the 3rd gear, but at least at 35mph (and/or almost 3k rpm) in opposite to normal "warmed up" shifting which can occur at much lower speeds/rpms.

hmm, I thought when the coolant is cold the ECU stops shifting into OD. Didn't realize ECU stops going into 3rd.

Maybe inspect the engine coolant temperature sensor too? At least check the readings when cold.

 

[fenixus]

This statement makes me worried.

This has never been a problem in the past though. What is the 'solution' to the 'problem'?

 

[JohnGD]

You should see the fluid turn crystal red with about 10 qts. So 3 gallons of Walmart Supertec dino ATF will do fine.

I wonder if there is an Advance Auto nearby their 40% off coupon code will give you a better deal. Use the rest to flush out the PS system.

Well, when i finally flush my radiator I am planning on changing it so...that would take care of any problem with that...

Any help with what I asked below, John?

 

[JohnGD]

Yeah, this part has me puzzled as well - the newly programmed ECU and ECT. The transmission shift points are electronically controlled. So it shifts when the ECU tells it to. Maybe that's what the ECU does.

One test is to probe the solenoid lines for ECU signals and the other is a resistor in place of the ECT.

I have a brand new OEM ECT for EFI sensor (old one had a dead spot around 50F) and it didn't change much.

also, even when car is dead cold, it actually will shift into the 3rd gear, but at least at 35mph (and/or almost 3k rpm) in opposite to normal "warmed up" shifting which can occur at much lower speeds/rpms.

 

[fenixus]

Unless someone proves it's all wrong on OP's and my car, I will assume that's what ECU does to help warm it up faster.

However, probing solenoid lines or cheating dead cold ECT/ECU with "warm imitating temperature" resistor sound like good tests to see, but I will personally pass on it for now. it doesn't bother me too much.

Yeah, this part has me puzzled as well - the newly programmed ECU and ECT. The transmission shift points are electronically controlled. So it shifts when the ECU tells it to. Maybe that's what the ECU does.

One test is to probe the solenoid lines for ECU signals and the other is a resistor in place of the ECT.

 

[JohnGD]

I'm not sure which series they are talking here, but looks like ECT temp < 122 degF causes a switch to open, much like manually turning off OD. So from this I'd say cold temp only affects OD.

But I agree, it doesn't really bother that much then no sense going into the wires.

There are a lot of good Toyota articles here. See Page 5, Figure 4-03:
http://www.autoshop101.com/forms/AT24.pdf

 

[CarryMeBF]

I'm not sure which series they are talking here, but looks like ECT temp < 122 degF causes a switch to open, much like manually turning off OD. So from this I'd say cold temp only affects OD.

But I agree, it doesn't really bother that much then no sense going into the wires.

There are a lot of good Toyota articles here. See Page 5, Figure 4-03:
http://www.autoshop101.com/forms/AT24.pdf

I haven't searched yet (I've been quite busy), but this may help troubleshoot.


http://tinyurl.com/br7b3hs

 

[JohnGD]

Ok, I'm still reading now. Looks like on Page 13 there is the 3rd gear shift restriction. :clap:

Looks like it's probably normal. Except I don't know how to explain OP's it didn't happen before.

I just hope p.13 isn't talking about the earlier 3-speed Aisin transmissions however.

 

[fenixus]

maybe worn out TPS is a problem here?

on page 10 of that linked article, it says the ECU based on TPS input, controls the shifting and lockup timing...

perhaps cold worn out TPS provides different signal than warm worn out TPS?

EDIT:
oh you beat me JohnGD, I've gotten to page 10 only hehe

so, it seems possible that V6 transmission models "cancels 3rd gear upshift" at light engine load until certain coolant temperature is reached. it is able however to shift into 3rd (same cold engine) when needed, e.g. under moderate engine load or Throttle opened wider or the VSS reading higher rpms or speed or any combination of those inputs (just guessing) ....

 

[JohnGD]

That should explain the higher shift point you experienced. These are generic but pretty good articles. hehe

 

[fenixus]

1 more article to consider:
http://www.autoshop101.com/forms/h16.pdf

it says the upshift to 3rd gear at 50% throttle is normal at 37mph, while in Power mode (if the trans has such thing, mine doesn't) the shift point occurs at 47mph.

so, the question is, to which gear it shift into when warm and driving e.g. 25mph? is it 3rd or rather Over/Drive (which is locked out when cold)?

 

[Nark]

I have an automatic 2001 Camry V6. I recently had my transmission fluid changed (01/11). Especially now that it is cold, it seems the first time (first use of the day) that my car shifts from 2nd to 3rd gear it requires me to get the car up to about 2800-2900 RPMs instead of what is usual around 2000 RPM. I can get it up to 2700 and it won't go, let off the accelerator and it will just run back down in 2nd gear.

After it shifts into the 3rd for the first time (during that drive when the car was started cold), then it doesn't do it again.

Any thoughts?

What if you warm it up to normal temp before driving?
Camry 3rd gear engage at ~100 F and OD at ~150 F so temp could be the issue.

 

[CarryMeBF]

I flushed out my transmission today via this link, and I will test it out tomorrow after a cold night. If the problem is still there, I will try to warm it up before and then drive and see if that makes a difference.

 

[fenixus]

give it 5 minutes of warm up time from cold start and keep the heater off during that time. wondering if it will be changing gears normally then. if so then nothing to worry about really.

I flushed out my transmission today via this link, and I will test it out tomorrow after a cold night. If the problem is still there, I will try to warm it up before and then drive and see if that makes a difference.

 

[ferrari]

I had the same concern when I purchsed my 98 V-6. Come to find out from 2 different dealers, the tranny was designed to cold shift from 2nd to 3rd at a higher rpm only once after start up to warm up or speed up the transmission to reach safe operating temperature. My V-6 has always shifted 2nd to 3rd at around 3000 rpm. Letting the engine warm up will not make the tranny shift differently. I have tried it.

 

[CarryMeBF]

Humm... Usually I think it takes place one time. But I have forgotten now.

 

[ferrari]

What I meant CarryMeBF is that it always initially shifts once at 3000 rpm. Then it shifts normally at a much lower rpm around 2000, unless given a hard acceleration.