1994 Toyota Corolla does not shift into higher gears if engine is not warmed up properly

My 1994 Toyota Corolla does not shift gears if the engine is not warmed up nicely. In the cold weather, the problem is much more apparent. If I start my car without letting it warm up nicely and drive on to the highway, I have to drive in the right lane at a max speed of 50 mph and everybody coming behind me curses and then overtakes me. After about 10 mins, the car then shifts gears and I am able to drive at 65 to 70mph. If it is extremely cold outside, I have to stop the car somewhere, let the engine warm up and then drive.

Also, I have noticed that the pointer on the temperature gauge on the dashboard is below the “C” especially when driving on a very cold day. When the engine is left running idle, the pointer does settle between “C” and “H” and as I start driving, it steadily keeps going towards “C”. The heater is also not that effective at that point.

I have asked a car mechanic but he did not seem to think there was anything wrong with the car.

I would appreciate any help on this.


Find another mechanic.

I’m guessing your Corolla has a thermostat stuck in the open position, and it’s not allowing the engine to warm up correctly. Not only does this provide you with little or no heat, it also wastes gasoline.

Automatic transmissions are programmed to stay in the lower gears a bit longer in cold weather, although your description sounds excessive. The cold engine may be contributing to this problem.

I’d install a new thermostat and have the cooling system flushed and refilled.

Has the transmission been serviced recently? Has it ever been serviced?

I have several Toyotas and those with automatic transmissions exhibit similar behavior until warm. On my Sienna minivan, the transmission will remain in lower gears for the first mile or so in cold weather until the engine reaches sufficient operating temperature. I researched this after I bought the van and was told that this is by design on most Toyota vehicles to help the car reach operating temperature faster for emissions purposes. There may be other reasons as well. Many Toyotas are apparently programmed to delay upshifts until the engine starts to warm, and this is only evident in cold weather. After ten years of owning this vehicle, the transmission still performs flawlessly.

The fact that your temperature gauge eventually rises but keeps going toward the “C” coupled with the low heat problem leads me to believe that you may have a thermostat issue that is preventing the car from reaching normal operating temperature, which, in turn, is causing the on board computer to delay the upshifts.

This is just a theory based on my years of experience owning Toyotas and knowing how they tend to behave until they reach normal operating temperature. This may not be your issue at all, but I would consider having the thermostat replaced and cooling system serviced if the car is running “cold” as you seem to be describing. The thermostat could be more or less stuck in an open position.

Get the thermostat replaced every 5 years when you get the “long life” coolant changed.

Get a new mechanic. That’s a fundamental no brainer for EVERY mechanic when someone reports what you just did. You’re getting no heat …needle dropping like a lead balloon … Shade tree 000/101 should have hit him in the head like a sack of nickles.

The trans issue may be coincidental. I think your trans is too old to have any relationship to engine temp beyond some converter lock up sequence. I’d say you just have some gummed up trans internals that don’t move right until you’ve warmed the fluid enough. I could be wrong, but this is not normal in transmissions of your vintage.

That is, someone in Canada …starting their car @ -30F …isn’t NOT going to shift until their engine warms up. That would be a total snafu on the manufacture’s part. Nope, I don’t buy it.

Consider an Auto-Rx treatment on the trans (google it) …but get that thermostat changed pronto.

I have owned 4 toyotas with autos and the more miles you put on them the longer it takes to shift into overdrive, this is common and 3 of them had over 200,000mi on them.
Yes you need a new thermostat.
Tell them you need on that lets you get warm heat faster from heater, there are 2 different thermostats.
Make sure they use new antifreeze.

Besides the thermostat, note IF the radiator fan is running when the engine is cold.

Thanks to everybody. I guess I should claim partial responsibility as to why the mechanic may not have been able to tell me what the problem might be. The reason is that I explained much better when I wrote down the problem. I probably did not explain very well - the only thing I mentioned to him was that the gears do not shift in cold weather if the car is not warmed up nicely.

Anyway, as per all your responses, I was better equipped to talk to him and I not only explained the problem better to him this time around but also let him know the possible solution. Got the car fixed from the same mechanic yesterday and it is now running like a charm.

Really appreciate all your responses. Thanks!

Agree with the other guys.

…And, the solution was to replace the thermostat, and to change the transmission fluid, and other stuff, wasn’t it?