My Toyota Highlander will not start when the weather is cold, mostly in the mornings, but it starts easily, when the weather goes hot in the afternoon. HELP

Replace the fuel injectors.

Don't worry about the smoke when your car starts it will mostly happen in cold mornings but as car heats up it should be gone its just cause the car has to heat up to a certain tempeture. Hope it helps.

in cold weather diesel gels up and sometimes causes a no start issue..a cetane fuel additive helps with this issue. if temps go below 20 degrees, add a quart per tankful of cetane to the fuel to help start on cold mornings. also diesels require more amperage to crank than gas engines do..thus a stronger battery is needed..

Behind the temp panel the wires or hoses are back words

This is most likely a noisy lifter (or valve tappet). In cold weather, the clearances in the valve train open up because metal contracts due to the cold. Once the oil pressure comes up after start the noise goes away because the larger clearance fills with oil and the lifter becomes "cushioned" with the oil. The proper fix is to have the valves adjusted. I believe in your model, that is done by putting shims on the lifters. This will quiet the noisy lifters. In the short term, you can try using a lighter weight oil for cold weather. This will get the oil to the lifters faster after start up and quiet the tapping more quickly. Once the weather warms again, shift back to the normal weight.

Check your battery for proper volts (12.6). Sometimes the cold weather will bring a battery down. Also check the Starter Relay, again cold weather will make it stick causing it not to start. Those are the biggest problems with a car not starting in the cold weather unless you have something else going on then your starter and your ignition needs to be checked.

Your cold start valve is not opening to assist the firing. It function is to provide extra fuel to ignite the all combustion chambers easily. When the engine doesn't have this extra fuel from the cold start valve, it will take a few times to get it going. The cold start valve is turned on at the time of starting only if the ECM get the signal from coolant temperature sensor saying it is at a preset level. When the sensor is bad, it can give a wrong value so ECM think that temperature is hot so not turning the Cold start valve. Replace this coolant sensor first, then the next thing is to check out the cold start valve.

You have a broken wire connection between the temperature control knob and the circuit board behind the center dash console. Vibration causes the failure and once the control knob gets loose the solder connection fails.

For someone that knows how to remove the dash unit and can re-solder a couple of new wires this fix should take no more than 1 hour. Make sure that you apply loctite to the heat control knob spindle nut when you re-assemble it.

The dealer quoted me 750 dollars to fix this issue and I found out that it's a common failure for this year. I fixed mine virtually for free but it took some tools and about an hour of my time.

You have a broken wire on the heater control potentiometer. You can either order and replace the control, which is expensive, or you can remove the control, and disassemble it, and re-solder the broken wire. We do this all of the time; resolder the pots bacjk on to the main PC board.

hi you will find that the cold start injector is not working it is found near the throttle bodyand injects fuel to start when cold like aq choke on older cars . it may need replacing i suspect that it is either blocked or just worn out they are not expensive