Criminalistic and forensic processing of vehicles damaged by fire is a specific field of crime scene investigation because the situation in terms of traceology is significantly different from the ones encountered when investigating other events and criminal offences. Due to the relatively small space of the car and a comparatively high density and flammability of fuel and other materials contained in it, the speed of development and the intensity of fire on such vehicles can be very high. This contributes to the fact that many traces that may indicate possible causes and origins of fire may be largely or completely destroyed. Bearing in mind this danger, but also the transience and unrepeatability of certain phenomena, it is very important to promptly arrive at the scene of fire and quickly extinguish it, as well as to monitor and record the development of fire, observing its characteristics. In addition to this, it should be borne in mind that in these situations the possibilities of proving by personal sources of evidence is minimal, so that criminal investigation must be based on material evidence collected during the crime scene inspection. The paper aims to point out specific traces in cases of spontaneous car combustion, particularly in cases where fire started in the area around the engine and in the passenger area.