Slight engine hesitation on acceleration about 1500rpm

[uk_friendly_fire]

K9 swb 1.5d regularly serviced.47k miles. Not noticeable on heavy acceleration. No DTC reported by head unit. Any clues what is causing this and a fix?

[Izzug]

All the time or just when cold or hot ?

[uk_friendly_fire]

It seems to happen all the time when acceleration is gentle building up revs hot or cold say in heavy traffic. But not noticeable if accelerating harder say pulling out right to cross a junction or moving away smartly at traffic lights.

[Izzug]

It seems to happen all the time when acceleration is gentle building up revs hot or cold say in heavy traffic. But not noticeable if accelerating harder say pulling out right to cross a junction or moving away smartly at traffic lights.

I have noticed a slight hesitation / flat spot at low throttle as you transition from idle control to throttle control. It seems more 'obvious' when cold. I just put it down to Citreon software, not a physical thing, is this a new thing?

[uk_friendly_fire]

I've had the car from new and I don't recall it happening when new. It might be since the last firmware update I did a couple of years ago. I think there is a new update to it issued earlier this year. I might install that.

[jj9]

I had a hesitation exactly like you are experiencing on a Renault 1.9 Dci a few years ago.

Turned out the hesitation was the EGR valve opening which reduces the power of the engine, it was only noticeable if you were accelerating gently from rest..... Blanked the EGR valve off and the hesitation was gone.

Cheers.


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