abbyNormal

I did a search and found a few posts that sort of match what I'm seeing but it wasn't clear in those posts if the issue was sudden or was there from purchase date. Also, I got the impression (in the other threads) that the car was drivable and mine is on the edge of not being drivable.

So here is my issue:
Washed the car last Thurs. Went around the block to blow excess water off. The last two or three stops I notice a hard surge forward when coming to a stop. I thought it was maybe just the brakes grabbing since they were wet. Dried the car and then headed around the block again and realized something is way wrong with my trans.

When slowing the down shift from 3rd to 2nd (about 8 MPH?) is abrupt and pushes you forward like you've stabbed the brakes. The down shift to 1st is very hard and almost locks up the rear end. It happens at like 2 MPH. I rented a car for a long weekend since I had company coming into town Last night I took the LS on the highway hoping something in the trans was just stuck and needed to get warm. No dice. Still jerks the car on down shift to 2nd and 1st. I have to put in neutral at like 10 MPH and come to a stop in neutral.

I do have the techstream software. I ran the few diagnostics I could (with the car parked). No codes or anything.

Anyone have an idea what's gone wrong with the trans and/or what I can do or test to narrow down this issue?

I know I pulled a bunch of wiring diagrams down from a site that I paid to get into for a day (I think). Going to try to find that site and see if I can pull down troubleshooting for trans issues.

If anyone knows of a good trans shop on the west side of Las Vegas let me know.

AN

abbyNormal

Looks like the site I used for the wiring diagrams was https://techinfo.toyota.com

yoitskenn

iTrader: (4)

Do a tranny flush.

rkw77080

Attached are something that can help you narrow your search for solution...

abbyNormal

I changed 8 quarts of fluid, 2 quarts at at time, last year. Car has 95k miles on it, so I doubt it's fluid related.

I had planned to do another 4 quarts soon. Looks like I'll be doing it sooner than I expected if I have to drop the pan.

abbyNormal

Thanks! I ended up pulling those down with a bunch of other ones from the TIS. Looking at the troubleshooting table, there isn't one for hard down shift 2nd - 1st (or 3 -> 2).

First thing I'm going to check is the brake light switch. Then I'll walk through some of these tests that have you checking switch/solenoid positions while driving.

abbyNormal

Can anyone verify a few things about the manual (sports shift) functionality?

1) If you set it 2 or 3 the car still downshifts to 1st on a stop

2) if you are slowing down with it in 2 and you select 1, you get an abrupt lurch as engine breaking in 1st kicks in.

Thanks,
AN

abbyNormal

Doing a little more digging around online, I get the impression it could be the ECU has packed up. Going to try some testing first but if I have to get an ECU, anyone recommend a source? Repair or replace? Also, I've got SmartKey, does ECU replacement affect that or is the SmartKey config stored in a different computer in the car?

AN

Howzit

Is it a early production 05? This sounds like the same issue as some of the 04's had. A reflash of the computer could fix it.

abbyNormal

I don't think this is the same issue. That issue has to due with the engine freewheeling when you slow down (or being in the wrong gear) and hit the gas correct? My trans was working perfectly until last Thurs. This issue makes it almost undriveable. I have to put it in neutral when coming to a stop or the rear tires nearly lock up when it shifts down to 1st.

Also, I'm pretty sure I checked and my VIN was after the need for a reflash.

Thanks,
AN

Bocatrip

What is your current mileage? Do you remember the condition of your transmission fluid when you had it changed at 95,000 miles? Was it discolored, brown, or bright red?

abbyNormal

Car has 95k miles approx. It probably had 94k when I was changing the fluid. I did it over 2 months last summer/fall. The fluid was used but not burnt.

The car was driving perfectly until I took it out after washing it last Thurs. I think either something in the trans is stuck or the ECM has "gone bad".

I ran the car down the highway with the Techstream stuff running last night. All temps and sensors that it reports looked fine.

I'm going to start probing connections at the ECM for the proper voltages and resistances tonight. My guess, at this point, is that trans solenoid SL2 is not being applied when it should, which enables engine breaking in 1st and 2nd.

AN

2KHarrier

You probably have thought of this already, but since the car was operating normally prior to the carwash, I would have to assume that something that happened at the car wash has either fouled or disconnected an electrical connector.

You have no codes stored at this point? Crawl under the car and see if any connectors appear to be disturbed or not in their correct location.

Not sure what else would be apparent just by doing a DVI under the car...

abbyNormal

I did think of that, but I didn't even spray under the car. When it happened Thurs, I rented a car and didn't start the LS until Tues, hoping, if it was a wet connector, it would dry out. No dice. I should go ahead and crawl under there just to check for dangling wires I guess.

No codes. I checked resistance and voltages at SL1 and SL2 and the ECM is applying the right signal at the right time. So my engine breaking theory is out the door, unless the valve itself is stuck.

I cleaned the MAF just because I had planned on it and was out in the garage anyway. I'll clean the Throttle body today and drive it for a bit. If things don't clear up, I'm going to end up taking it to dealer I guess.

If anyone know of a (trans) shop in Las Vegas (preferably the west side), that they would recommend, please let me know.
AN

Howzit

Any update?