Hdi Engine Speed

[C4VTS]

I have noticed that my engine speed seems to suddenly jump from about 2000rpm to about 2,300rpm when I accelerate fairly hard in 3rd or 4th gear and the engine sounds a bit like it has an an automatic gearbox when it does it. When I look at the rev counter you can see the speed jump a few segments.

 

I don't think the clutch is slipping as the road speed also increases when it happens.

Also I am not sure if this is a problem or perfectly normal. :D

 

Has anyone else with a 2.0HDi engine or even a 1.6 noticed this?

[Z3M Roadster]

Nope, only thing I have noticed is when you try and pull away quickly the car accelerates and then the engine revs drop and you lose all power, making it pretty dangerous on roundabouts. This also happened on the 1.6hdi courtesy C4 I had. Again Citroen deny all knowledge, but it is probably beyond them as the answer can't be obtained by plugging it into a computer.

[incubus]

I have noticed that my engine speed seems to suddenly jump from about 2000rpm to about 2,300rpm when I accelerate fairly hard in 3rd or 4th gear and the engine sounds a bit like it has an an automatic gearbox when it does it. When I look at the rev counter you can see the speed jump a few segments.

 

I don't think the clutch is slipping as the road speed also increases when it happens.

Also I am not sure if this is a problem or perfectly normal. :D

 

Has anyone else with a 2.0HDi engine or even a 1.6 noticed this?

 

 

I have a 1.6 HDI VTR+ that does just that...! I have always put it down to a "3rd gear Overboost"..! To be honest i coud'nt live without it... :) If it is'nt normal then i dont want mine fixed... :)

 

.......

 

<_<

[lee_marshuk]

oooo you have just answered my question. Mine does that too, I'd booked it in as a fault. It's weird, it even does it in cruise control (i.e. your speed at 40, you set cruise at 70, press unpause and let the car accelerate).

[C4VTS]

Hi Lee,

 

When is yours booked in?

 

I would be interested in Citroens response to this.

[wozza]

Its likely as he says the HDI's have an Overboost function which gives you a bit more torque when you put your foot down.

 

http://www.citroen.com/CWW/en-US/RANGE/Pri...OTORISATION.htm

 

Hopefully that link works. Tells you what is what.

[C4VTS]

Its likely as he says the HDI's have an Overboost function which gives you a bit more torque when you put your foot down.

 

http://www.citroen.com/CWW/en-US/RANGE/Pri...OTORISATION.htm

 

Hopefully that link works. Tells you what is what.

 

HDi 110 bhp DIN

"It supplies maximum torque of 240 Nm at 1,750 rpm.

Torque can be increased to 260 Nm at 1,750 rpm on the three highest gears, thanks to the overboost function.For strong bursts of acceleration, the "overboost" function kicks in, delivering up to 20 Nm of additional torque by increasing the fuel injection rate. This new engine therefore combines a fast response with a linear increase in power, and excellent acceleration at low engine speeds."

 

HDi 138 engine

Offering maximum torque of 320 Nm at 2,000 rpm, it also features an overboost function that raises torque temporarily to 340 Nm.

 

 

It does seem to make sense now. :D

[skaramanga]

So basically, we're all worried that our cars are too powerful! :D

[Stuey]

So basically, we're all worried that our cars are too powerful! :D

never thought I would see that written <_<

[lee_marshuk]

Ha ha!! Yes that was their response too. Weird that I've never noticed it before, but nevertheless apparently normal!