Toyota 2003 Car of 85kW 2.0 D4D diesel. Who have a similar experience with some of these engines. The problem is this: if the engine is warm and then lowering the engine speed, the car starts to twitch. The car starts to lose power. When holding the accelerator pedal at the bottom, nothing happens. Motor is thinking for 5-10 seconds, then throws a cloud of black smoke from the silencer. When the engine is cold, there is no problem. Cold start, idle, and acceleration is very good with a cold engine. When the engine reaches the normal operating temperature, the problem reveals. Then again, sometimes I can drive for a long distance with a warm engine, without that problem. Toyota service said that the problem is the engine nozzels. I switched off all four nozzles, which were very expensive. But the problem is still the same after that. So the nozzles were not causing this problem. Waiting for detailed advice.

SOURCE: Power loss in 2004 Corolla Verso D-4D T2 at speed

change your air filter

SOURCE: i have a problem in my toyota echo car 2000 model 2NZ - FE engine

throttle position sensor or called tps

SOURCE: Power loss in 2004 Corolla Verso D-4D T2 at speed

You might want to check the MAF sensor(Mass Air Flow) and clean it with MAF/MAP cleaner. I am also kind of puzzled with this problem as I have a 2004 Corolla also, I only had power loss when my MAF went bad.

SOURCE: engine light,poor acceleration and bucking from engine

The evaporation canister can cause this, so would any vacuum leak. A faulty throttle position sensor or camshaft position sensor would also cause this but it would in the diagnostics most likely.

SOURCE: High idle speed when the engine is cold

The high idle speed at start up is normal. As the engine temperature increases, the engine idle should kick down automatically. Insofar as the emissions results, if there were a problem, the check engine light should be on. If it is, take the car to an autoparts store and have the fault codes read. Most parts stores will perform the scan for free. If the check engine light is not on, and the idle question was all you were worried about, you are good to go! Hope this helped and best wishes.