I really liked these suggestionsHey, have you taken a look at your timing belt (visually check tension) and with a mirror can you get eyes on the tensior? (Should have a indicator point which will tell you if it’s hard/soft)
The reason I suggestion is, I recently experienced a rough idle, reduced power, poor start then crank with no start
Checking my book about Diesel engines, I realised the early warning signs I missed pointed to timing belt which right enough, on checking has lost tension.
Poor fuel consumption, misfire and knocking could be early warning of timing belt losing tension. A visual inspection (depending on the engine) should be fairly straight forward and free.