Slight hesitancy on Hdi

[C.J.]

The Xantia 2.0 Hdi has recently started a slight hesitation.Only happens occasionally on light acceleration, but slightly disconcerting as i know this sort of problem is not going to go away.

Any thoughts on the likely reason?
Fuel filter p'raps?

Just passed it's mot yesterday with flying colours. The tester commented on how clean it was underneath for a 100 thousand miler. One of the best he'd ever seen in fact!

Lovely car, and absolutely no regrets so far after 3 months of ownership.

[uncle buck]

The hesitation that you are suffering seems to effect a lot of modern electronically controlled diesel engines.
My 1.9 DCi engined Renault Laguna suffers from exactly the same problem (along with countless others)....there are posts all over the Internet reporting this hesitation on all makes of cars.

I got rid of the problem by disconnecting the ERG valve...I pulled the electrical plug off it & the hesitation was instantly gone. Strangely no engine management light came on with the valve disconnected, although other Laguna owners have reported that theirs did.

I have read reports that the hesitation is due to the MAF (Mass AirFlow Sensor) being dirty or just getting old...some reports say that by replacing it the problem was cured...some don't.

I'm not sure exactly what causes this hesitation but I do know that the electronically controlled Diesel engine is nowhere near as reliable as the mechanical system that it is replacing.

[Stunned Monkey]

I have read reports that the hesitation is due to the MAF (Mass AirFlow Sensor) being dirty or just getting old...some reports say that by replacing it the problem was cured...some don't.

Mine started hesitating and eventually got worse and worse, and the MAF sensor was to blame. The thing most noticable for me was when on very light throttle going down hill, the ECU couldn't make up its mind whether I was engine braking or accellerating, and it'd start to kangaroo very gently.