C5 Mk2 1.6hdi 110bhp Flatspot

[hake]

C5 Mk2 1.6HDi 110bhp suffers from intermittent brief hesitation of power output which always resumes almost instantly. Seems to happen at around 2000rpm to 2500rpm when accelerating. My imagination has it that the ECU is getting confused: I drive with a very light right foot. The behaviour has been with the vehicle almost since new. After a recent 25000 mile service, the problem was dormant for two weeks until I had done a long motorway run whereupon it returned. I understand that the ECU adapts to the way the car is driven.

 

No problems have been revealed by the dealer's diagnostic equipment (surprise?).

 

The general engine performance is magnificent. Torque is amazing and the engine pulls strongly from 1100rpm. Power at speed is very good for such a modest capacity engine. Fuel consumption is around 50mpg.

[citroeneddie]

Hake

 

Can't say I've really noticed about the flat spot, but it has been mentioned before.

 

For the last 7k miles I have averaged 61.3mpg.

[kfk]

C5 Mk2 1.6HDi 110bhp suffers from intermittent brief hesitation of power output which always resumes almost instantly. Seems to happen at around 2000rpm to 2500rpm when accelerating. My imagination has it that the ECU is getting confused: I drive with a very light right foot. The behaviour has been with the vehicle almost since new. After a recent 25000 mile service, the problem was dormant for two weeks until I had done a long motorway run whereupon it returned. I understand that the ECU adapts to the way the car is driven.

 

No problems have been revealed by the dealer's diagnostic equipment (surprise?).

 

The general engine performance is magnificent. Torque is amazing and the engine pulls strongly from 1100rpm. Power at speed is very good for such a modest capacity engine. Fuel consumption is around 50mpg.

 

Your dealer is correct in saying that the ECU adapts to your driving style, whether the problem is with your driving style or the vehicle though is another matter.

 

I know of several customers who drive as you put it 'light footed' and have complained of hesitations at certain revs, interestingly though never of fuel economy problems.....and as per your experience, reinitialising the computer resolves the issue for a week or so.

 

A characteristic i'm afraid.