له شدن یا گرفتگی فیلتر روغن

The oil filter restricted or its element collapsed, obstructing flow. Most filters have a bypass valve for exactly this, so a blocked filter usually means unfiltered oil rather than no oil — which protects the bearings and stops protecting them from debris.

A collapsed element is the worse case and can restrict genuinely, dropping pressure under demand. The usual causes are a filter far beyond its interval, a very cold start with thick oil, or a poor-quality filter whose element is not up to the pressure. Cut the old filter open where a pressure fault is suspected — what is in the pleats says whether this was neglect or something upstream shedding debris, and that changes the repair.