Auto transmission shifts way too quickly... Please Help!

[flyin1]

Hey guys, I need your input.

I have a 1985 Toyota Tercel Hatchback, and recently I replaced the original carburetor with a used one with only 88,000KMs on it... I switched it up because I thought it would be better knowing it has less wear on it because my Tercel has 250,000KMs...

So to the problem:
The replacement carburetor works very nicely during cold starts and warm starts, BUT in operation, However, I immediately noticed that my Auto Transmission shifts WAY too early... by the time I get to 45KMs I'm already in 3rd gear.

If I FLOOR the gas pedal, it also doesn't want to downshift as well...

Also, when switching from 2nd to 3rd, the gear change is hardly noticeable.... No sensation...

Before replacing the carburetor with this one, it shifted perfectly...I know it is not a Transmission Problem,... I know it is something up with this carb...Does anyone have any input on what specific thing is going on?

Thanks guys

[Petros]

there is a kick down linkage that goes from the right side of the trans up to the throttle bell crank, it sounds like either yours was not installed when you changed the carb, or it needs to be adjusted for the new carb.

There is a Service manual procedure to adjust it, it is not difficult. First verify that it is connected. If not hook it up and take it for a drive, that should solve the problem.

The replacement carb should have the same lug on the throttle bell crank (the part of the linkage that the throttle cable attaches to) which I have seen on both auto trans Tercels, and manual trans Tercels. If for some reason you do not have the lug that the kick down linkage attaches to you will need to swap the bell crank from the old carb on to the replacement one.

Simple enough, good luck.

[Mark]

What Petros said. I had a similar problem once. It turned out that that linkage from the carb to the auto transmission (on the passenger side of the trans) had come apart. Yours might not be connected or if it is, it is too long or short (I can't remember which would cause early shifting). There's a turnbuckle on the linkage that you can turn to make it longer or shorter. There's a mark on the transmission that a point on the linkage is supposed to point to when the throttle on the carb is full open.

[Mark]

From the manual:

trans link.jpg

[Petros]

I learned this when I changed a head gasket on a T4wd with an auto trans, got it all together and completely forgot about the linkage, I was happy to have it running again (I was on a road trip and did the head gasket in the back of a parking lot!). As I drove off, I noticed the lack of kick down, with the engine bogging down on acceleration. That was when I remember the kick down linkage. Once I popped it back on to the bell crank on the carb it drove normal again.

[flyin1]

thank you guys for your input!

This really helps me a lot