Renault Master Problems: Common Issues & Fixes

Hello fellow mechanics.

I have a Renault Master 2.5 dci.
Kann es sein das die Abregeldrehzahl bei ca. 3750 Upm liegt? Liegt das am Motor von Renault? Oder liegt das an dem Ort wo der Motor verbaut ist. So, about the bus.
I mean that the bus shouldn't be able to reach such high speeds because of the load from heavy weights. Does anyone have this engine in a passenger car?
'3750 RPM seems a bit low to me, as my Golf and other diesel engines I know typically rev up to just below 4500 RPM.'

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Golfmann wrote:

Could it be that the charging speed is approximately 3750 RPM?

Hi,

It seems the term "Abregeldrehzahl" is being used again without a clear definition.

While I don't know of any "official, binding definition," at the AU (vehicle inspection), a certain engine speed is also checked. The resulting speed is where the fuel injection amount and the sum of engine losses balance each other out, even with full throttle. For TDIs, this is typically around 5000 rpm.

Of course, this is different from the rated speed, above which the power output drops off so sharply that not only does the torque decrease, but also the useful power output plummets.
And this speed, for example, is also 3750 rpm in the ALH-TDI engine.

Thank you for the clarification.

I just had the feeling that the engine's rev limit was being electronically restricted. The power delivery is excellent up to that point. However, it's not a major issue because the overall gearing already allows for a top speed of 160 km/h at that RPM.
allows. And that's quite enough for a bus.

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diesel.gustav wrote:

You will hardly find a relatively modern TDI or CDI van with the rev limit you mentioned, which is approximately 5000 RPM. However, it's possible that I missed one. Which one is it?

Hello Gustav,

I'm not familiar with the van segment.
I can hardly imagine that the "my engine's idle speed" (AU-test) would be below 4000 rpm.
If so, I would be interested to know what the rated speed (Pmax) of these motors is.