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What is Dieseling in a Car?

Dieseling is the effect of spontaneous ignition of the fuel mixture in the combustion chamber of a gasoline engine due to a significant increase in the compression ratio. The result is that the engine continues to run after the spark has been cut off.

The name “dieseling” is similar to the ignition principle of a mixture in a diesel unit. The main symptoms of diesel are:

  • the gasoline engine does not stall after the ignition is turned off, while the precarious operation of the internal combustion engine is noted ;
  • the revs are low and float, a ringing metallic detonation knock is heard ;

Dieseling by the nature of the manifestation of a malfunction has a certain similarity with SC ( glow ignition ). You should note that in the case of a short circuit, the motor sometimes continues to work after the ignition is turned off as a result of significant overheating (contact of the mixture with hot surfaces or carbon deposits in the cylinders). Concerning diesel, such a malfunction is caused by a significant increase in the gasoline engine’s compression ratio.
The diesel engine problem can arise due to interference in the internal combustion engine design, unqualified repairs, and strong carbon formation. In the latter case, deposits reduce the working volume of the combustion chamber.

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