diesel knock

diesel knock

[′dē·zəl ‚näk]
(mechanical engineering)
A combustion knock caused when the delayed period of ignition is long so that a large quantity of atomized fuel accumulates in the combustion chamber; when combustion occurs, the sudden high pressure resulting from the accumulated fuel causes diesel knock.
References in periodicals archive ?
Good sound insulation has obviously been a consideration and although there is a bit of diesel knock under severe acceleration it is otherwise a quiet runner with a minimum of road and wind noise coming into play.
Power flows seamlessly to the wheels and even on tick-over there is no diesel knock.
Noise levels are impressively low and even at start-up there's barely a sign of the once-familiar, low-speed diesel knock.
Despite being a diesel there is hardly any diesel knock, and wind and road noise are well suppressed.
I'm not convinced the efforts to reduce diesel knock are totally successful because the engine in my test car could be quite noisy initially.
You can't entirely get rid of the diesel knock at tick-over, but once under way the Alfa sounds and performs as well - if not better - than its petrol brothers.
But the model I drove had done just a few hundred miles so, like all diesels, it would bed in and diesel knock would reduce.
Even when I started the Xsara up in the morning there wasn't the usual diesel knock from under the bonnet.
0-litre turbo diesel knocks out a healthy 134bhp, which gives it a 112mph top speed and acceleration to 62mph in 11.