Why is it difficult to start a diesel engine after it stalls when hot?
3 Answers
Regarding the specific reasons why a diesel engine is difficult to start after stalling when hot: 1. Excessive carbon deposits: Carbon buildup can cause incomplete fuel combustion, leading to engine shaking. The impact of engine carbon deposits on vehicles is significant, primarily by reducing engine power, resulting in uneven and gradually diminishing power output, leading to insufficient power. 2. High fuel consumption: Increased fuel consumption adds to your financial burden. 3. Low ambient temperature: Extremely low temperatures make starting difficult, causing ignition problems and making it hard to start the engine. Severe carbon deposits in the combustion chamber can also lead to cylinder knocking, produce noise during low-speed acceleration, damage pistons and crankshafts, and cause engine overheating, severely compromising vehicle safety.
I've been driving diesel cars for over a decade and often encounter the issue of the engine not starting after shutting down a hot vehicle. The main problem is that the engine gets too hot, causing the diesel to vaporize easily, which leads to the formation of bubbles in the high-pressure fuel pump, resulting in poor or interrupted fuel supply. Another possible reason could be the deterioration of the injector's sealing performance, where the sealing rings expand and fail under high temperatures, causing fuel leakage. Additionally, air entering the fuel lines can worsen due to thermal expansion. I remember one summer when my car wouldn't start easily after being shut down. Upon inspection, I found that the fuel temperature sensor was inaccurate, causing the ECU to misjudge the fuel supply. My suggestion is to wait a few minutes for the engine to cool down before attempting to start it again. If the problem persists, it's advisable to check the fuel filter or take the car to a professional shop to test the fuel system. After all, this issue is related to driving safety, so don't push your luck.
As a diesel vehicle owner, I've noticed difficulty starting after hot shutdown, primarily related to thermal expansion and contraction: High temperatures cause diesel evaporation or bubble formation, interrupting fuel supply; the injection pump may leak due to thermal deformation; air entering the fuel lines is more common when hot. Additionally, the starter gear experiences thermal fatigue and slips under high temperatures, while the battery faces increased load, worsening startup failure. Recommendations include regular maintenance of the injection system, checking fuel pressure and sensors; idling for a minute or two before shutdown to allow cooling; if issues persist, consider upgrading cooling components or having a technician scan for fault codes to quickly resolve before major repairs are needed.
