Mine did that too except at 45+mph, turns out I overfilled the transmission.

 

I'll double check the fluid, but the level does not seem to make any difference. When I initially filled and road tested, after testing the fluid was a bit low. I topped it off but no change.

I'm reading the service manual now, but I don't know exactly what to look for. Is this considered a problem with engine braking?

 

I would check the transmission cable adjustment and reset the battery, then work from there. What fluid did you use conv., blend or synthetic?

 

I used conventional fluid because I did a flush, will put in the good stuff when I'm done. I checked the throttle cable, it seems fine. But I did notice that when I pull on the tranny cable, I hear a bit of a noise coming from the transmission is this normal? Like a slight buzzing sound.

The battery had been pulled for some time when I was doing other things to the car so I doubt doing it again will help. I did another road test, the RPM drop happens in 3rd and 4th gear only.

 

I don't think its normal, but if the transmission shifts fine, I wouldn't worry.
What was the condition/color before you changed it?
I was wrong I still have the RPM dip like you said, but after draining some its not that noticeable anymore?
This was my problem. Is this whats wrong?
skip to 1:30:thumbsup:

 

Thanks for the video

It's like that, but more pronounced. As soon as I take my foot off the gas, the RPM's drop like a rock, to about 1000. I tried to take a video but my camera is screwed up, I'll trying using my phone even though the quality is terrible.

The condition of the fluid was not that bad, but there was quite a lot of metal in the pan and on the magnets. But I've seen way worse, I'd say it was about normal for a poorly serviced transmission.

 

Sounds like the one-way clutches at work and normal. You can verify by driving up to 30 in the "2" position. The typical shift point from 2-3 is around 25, so going 30 in 2nd is fine too. The "2" position engages an additional brake band meant for downhill engine braking. Without it the engine free wheels, this is to help MPG.

As far as RPM coming up quickly my guess is downshifting. Try a longer stretch of the road and just let it coast and downshift from 55MPH for 4-3 downshifts or even down to 2 if you can all by itself. You should be able to tell better away from the shift points. Also, accelerate gently and take note of the shift points.

 

Thanks for the info. It's hard to convey what the tranny is doing without actually being in the car. It just "feels" off on lift throttle, imagine putting the car in neutral then back into drive, that's what it feels like. Or to put it another way, the engine is turning slower than if there was a direct connection to the wheels, which corrects itself in a second or two. I realize every auto transmission does this, but it's so much more noticeable in this car.

The way I replicate it the best is to drive down a gentle slop, lift the gas, and that's where the tach drops sharply, then the tranny "engages" again. If I drive at just the right speed, it will do this quickly, on, off, on, off once every 2-3 seconds.

Okay here's a video I took. When the tach drops, then comes back up in revs, that's not me getting back on the gas. Turn the sound down it adds nothing :lol:

 

Yup, just like what happened/happening with mine. I really haven't found a definite solution, but I am going to try a blend next time. Did you do the diff also?

 

hmmm, my V6 usually drops RPM to around 1,200rpm when I left the gas off, not sure yet if that's normal hehehe.

anyways, just 1 note for 71corolla, not sure what it means though (upshifted gear?):
man, your RPM seem very low for driving at 70mph!

I usually have 2,500rpm at 70mph and almost 3k at 80-85mph on both cars.

EDIT:
wait ... never mind. you have KM on the tach not miles, right?

 

man, your RPM seem very low for driving at 70mph!

:lol: :lol: I wish.

That would be 70 kilometers per hour, or about 42mph. Saw your edit, yea speedo is in Km/h.

 

Yes I did the diff. Although no matter how hard I try, I can't find a definitive answer if the A540E/A541E shares fluid with the differential and transmission. No matter, I drained the diff and filled it.

I'm going to try a better fluid in a few days, like I said I used the cheapest Walmart fluid to do the flush. I doubt a different fluid will make any difference but maybe it will surprise me.

 

Me too, my auto tech teacher said they do, but he is a Honda tech. I used SuperTech also, didn't noticed a difference. I'm planning on using Valvoline MaxLife next time. Hopefully its goes away, kinda of feel like the car is pulling back(or forth) when you release the pedal. Right?

 

Ok, that does look different from the other video by Pmesfun, which looks like normal free wheeling and downshift.

Are upshifts all fine? How about trying with OD off?

There is a shift point around there, but I'm not sure if the ECU decides to downshift a little high. It will depend on engine load calculation as well.

 

Ok, that does look different from the other video by Pmesfun, which looks like normal free wheeling and downshift.

Are upshifts all fine? How about trying with OD off?

With OD off the behaviour is the same, which surprised me for some reason. Upshifts are fine, shifting in general is great as long as there is some throttle involved. It shifts smooth and silently, you can hardly tell when it shifts gears. It's only on lift throttle when it starts acting up.

edit - I want to clarify. In that video, all I'm doing is driving at more or less a steady speed, then lifting up on the gas. When you see the tach drop, then recover back up, that's without me touching the gas. After the revs come back up, I then get back on the gas. Although at the very end of the video I was slowing down, then did dip into the throttle right away.

 

I had my intake plenum off, so it's likely my cables are not adjusted properly. After thinking about it, what the manual is saying is, the cable needs to sit right on the stop, and not be pulled at all by the throttle.

OT, but after doing the timing belt, plugs etc. the 3VZ engine sure does purr. It has a different flavour than the 1MZ, such a wide power band and a different tone. the 1MZ sounds more like a traditional V6, the 3VZ has more a constant, smooth hum to it. And it loves to rev.

Still have to do the airflow and timing trick to get that extra few ponies. But I need to find my oil leak first, it drips on the exhaust which is very annoying. It's either the oil filter adapter, the oil pan, or the rear main. Hope it's not the crank seal. :ugh3:

 

I was slightly disappointed after I replaced the tb, wp, plugs, wires and cleaned everything. No noticeable power increase, better MPG though.

 

I'm tempted to try a leak stop, but most just swell the seals temporarily. I changed the oil and put in some Seafoam in the crankcase, that might stop the leak over time by cleaning off the gunk on the crankshaft and the seal itself. Or the seal could just be worn and dried out from lack of proper oil changes.

 

Don't leave the sea foam in there too long, I just put it in at the beginning of the day then drain the oil later that day.

Did use stick to conventional? I would use Castrol GTX High Mileage.

 

I'm not all that picky about which synthetic I use in the older Toyota engines. I use what I an find on sale. I have 3 jugs of Castrol Syntec 5W-30. I don't run oil long enough to justify using the more exotic oils. I would love to try a 0W oil though, when it's -30 the car barely turns over and it sounds like pure torture for the first couple of minutes.

In my Lexus I'm going to use a high end oil next time, although the 1MZ seems to really like the Syntec stuff.

 

I used GTX HM for about 3 OCI, then Syntec Blend, now I using Valvoline Syn Power the 1mz loves it. I might try Castrol Syntec or M1 HM next.

 

Canadian Tire had the Castrol 5 liter jugs on sale for $26.00 which is why I bought 3 of them. I should have bought more actually they are normally $42.00. They sell Amsoil now as well but it's $14/liter. Speaking of Canadian Tire, when I lived in PA and Jersey, that is the store I missed the most. There is nothing like it in the States.

 

My 93' does the same thing, and it had a new, yes new, transmission installed by a dealer, 37K, Km. and 3 years ago. When I got the car I tried to check the Trans. fluid level using the owners manual recomm. procedure. All I could get was splash all over the dip stick. I have since changed over to Redline Synthetic ATM fluid (myself) and get the same splash/check problem along with the same rpm wondering in that speed range. At the change I added less fluid than was in it before, but maybe my level is still to high? I think the fluid capacities possibly don't represent much of a guide for how much fluid you will have to put back in after a basic pan drain and refill. Alot of fluid must remain up in the valve bodies, etc. I'm going to try draining some fluid out.
I always assumed this was just a slightly annoying characteristic of the transmission and had something to do with the torque converter not being locked up.

 

If it splashed all over the dipstick, then it is probably overfilled. That why the better method is the manual transmission's fill/drain bolts that many new automatics are using. The only problem with those is the temperature range you have to be in to check the level and the pan has to be level, which can be a pain.

The A140 takes about 2.6 qts (not including the differential, which is about 1.7 qts). How much did you put in?

 

I'd interested in trying coasting from 100 Km/hr down and see how it behaves. This takes it high above the TCC lock up point (80 Km/hr) so as you steady it you should see the TCC lock up and the RPMs drop. Then as it coasts and slows down the TCC releases (RPM goes up). And then the gradual decrease and downshifts, etc.

The shift points are decided by the ECU on these transmissions. The throttle linkage only changes line pressure and mainly affect the quality of shift.

 

Next time I'm on a stretch of road that allows those speeds I'll give it a try. I was driving today at about 85 km/h and the converter definitely was locking up like it should. I didn't have a chance to pay much attention to other aspects though.

 

now you make me paranoid about how tranmission works on my V6 LOL :lol:
... and all I know since I rarely drive it long distance now, is that I slightly overfilled it *sheesh* ... in my developing paranoia I was even considering the transmission causes my low MPG ... no I'd better forget about it and get back to checking damn dragging brakes (still can hear it, less but still)

one thing about draining and refilling a formerly overfilled transmission (based on 5s-fe / A140E). somehow magically all you can drain out is always the book amount, so you would think it needs to be refilled per book, eh?
well, no, if it has been overfilled in past then you need to refill less (guess the amount).

in other words, once overfilled you won't be able to drain the extra amount out haha, only thing that fixes it is to refill less. and trust your dipstick only when car is HOT and ambient temperature is above 0C/32F otherwise you will get bullshit results.

 

now you make me paranoid about how tranmission works on my V6 LOL :lol

Don't worry if you had this problem you'd know!

Is 4.1qts, with draining the diff also?

That sounds about right. The owners manual says 0.9 liters for the differential which is almost 1 quart.

Went for a spin just now to the store. Before I did, I leaned out the airflow meter by 3 clicks. Definitely made a difference, but unless I'm imagining things, it made the transmission quirkiness worse. So I'm wondering if this is not really a transmission problem at all, or if it is amplified by a too lean engine under lift throttle? Could this be an EGR issue partially?

Either way this problem sucks, it's impossible to drive the car smoothly down a gentle slow at a constant speed, the revs go up and down, almost like the engine is dying then catches on again. :facepalm: Well at least I don't have mice problems, what I do for my Corolla (it sits most of the time) is use bounce dryer sheets, I put them all over the car in and out. Mice (and insects) hate that smell for some reason.

 

Is 4.1qts, with draining the diff also? I put in 3/4 of a gallon jug and 1/2 of another, then last week I drain, some but its still past the full mark. Need to drain more tomorrow. Also, a mice decided to rip the loom off various engine harnesses in both cars.:facepalm: Need to get PET loom and heat shrink now.:headbang:

 

owner's manual on A541E (usual for 1mz-fe) says the 4.2 qts is for both (they don't even mention there is a differential *sigh* haha).

so the drain & refill capacity of both should be around what you've got.

 

3.7 qts shows on Autozone's specs.

I've heard "up to 5 qts" but that is too much.

 

Autozone shows a differential capacity of 1-2/3 qts. But the A140 has 3 different differential sizes. So fill until it trickles out the fill hole.

 

So just removing the pan plug gets out about 3.2 qts. Oops. dipstick reads about 3/4 inch past the full mark when warm.

 

The Avalon uses the A540 series.

Drain the differential too. And then fill in 3.7 qts as a starting point. Idle the car until the radiator fan comes on once. Then check for the fluid level in the HOT area. Add 8oz at a time as needed and check after a couple of minutes (otherwise you see only smears on the dipstick).

 

I've made progress on this problem. If fact, I've essentially solved it.

The problem is actually being caused by the throttle position sensor. What I did was loosen it, and turn it clockwise a little bit. This completely cured the rapid RPM drop, and the hunting and jerking back and forth on light throttle or coasting. On my way home I stopped at the salvage yard and picked up another one. I marked the unit in relation to one of the screws, and installed it in exactly the same position as the donor car. The problem returned. So I turned the "new" sensor clockwise somewhat as well, and that did the same thing as the first, no more issues.

When I got home, I checked out the FSM, and this is what it shows:

I tested the original and the replacement unit, they both show basically the same problem. Instead of ~2 ohms, I see about 40 ohms. When I rotate the TPS slightly, it goes down to about 10 ohms. By pressing on the center, the reading fluctuates, which it shouldn't.

So what I think is happening is, the ECM is getting confused, because at rest, the TPS is not giving a correct reading. And it may be intermittent when some current is running through it, a test meter has almost no current. So by rotating the unit a bit, it's putting it back into a range where the ECM considers that idle, or closed throttle. I would imagine that these things spend most of their life at or near the very beginning (lowest resistance) of their rotation. So that is where they are going to wear out.

I don't know exactly how the ECM uses the TPS in relation to the transmission controller, but it clearly uses it at one of the inputs. The difference when it works is night at day, the car drives completely differently. The car feels normal finally. I have a feeling this is a pretty common problem actually, I can see these things wearing out on a regular basis with unintended results.

Here is the part number: 89452-32060 $144.18
Doing a search suggests that it can be replaced by this: 89452-22090 $74.08

Notice the 2nd part is half the cost, but I can't say for sure they are interchangeable but the info in this thread suggests so.

Here's the original part from the car -

 

so cool you found the true reason!

are you going to get a new OEM sensor from dealer now? or you stay with the adjusted old sensor?

my '02 solara sle V6 uses this part number (per toyodiy.com listing) 89452-06020
Toyota Part 89452-06020
Toyota SENSOR, THROTTLE POS
Retail Price: $61.36 Your Price: $45.71 per toyotapartseast.com

have no idea if it would fit your car and ECM.

quick check with toyotapartsoutlet OEM catalog shows that Part number 8945206020 was superseded by part number 8945233030 and this fits:

all V6 and i4 gen4 camry (1mz-fe and 5-sfe) 97-01, as well as 02-03 solara V6, 98-03 sienna, 97-02 avalon, 01-03 highlander and 01-03 RAV4.