Audi 80/Avant (B4)

Since 1991-1995 of release

Repair and car operation

The absolute border of frequency of rotation is approximately at level of 6700 rpm. Most later after that numbers of turns of a spring of valves start to fluctuate so strongly that any more do not provide faultless opening and closing of valves. Springs of valves can come off that leads to such consequences, as collision of the valve with the piston and, thereby, to serious breakage of the engine.

That business did not come so far, in engines Audi restriction of frequency of rotation which in case of approach to the named range of number of turns stops the further escalating of frequency of rotation by the termination of receipt of fuel is built in.

So if you already had to be surprised to faults in engine work on very high turns know are at all malfunctions, and the built in self-defence of the engine.