Fault codes THP Issue

[Ds31981]

Hi Guys
Just got a Ds3 D sport + THP model.
It’s a 2011.

The car has done 50k miles it’s had £2000 spent on it over last two years, in 2023 @44k miles it had full timing chain kit replaced.

When I got the car it was in a limp mode when I read the codes it showed 2 permanent faults
P2178 & P2191.

I’ve cleared the codes and now it drives fine although it seems a little hesitant not overly noticeable but it’s there.
Codes haven’t returned I’ve done 30 miles ish since clearing them.

Surely the chain hasn’t gone again in 6k miles has it? There is no rattle at all.
Any ideas?

[xantia_v6]

If the hesitation is just off idle, particularly when the engine is cold, it is possible that it is just a problem with the auto-adaptive mixture control map, which has learned some bad values. Try deliberately operating the engine for a few se3conds at a time at the throttle position where the hesitation occurs, and see if the behaviour improves after doing this a few times.

There is also a throttle calibration procedure which resets the mixture map, but your diagnostic tool may not be capable of running the procedure.

[Ds31981]

Hi,
Thank you for your reply, ok I’ll try that. I have a fairly decent launch diagnostic machine which can do quite a bit so may look into it later once home thank you.

Mine is a 2011 I read that the bad chains were on card pre09 is that correct? Mine has only done 50k miles and had it replaced already.
As long as it’s not chain gone again I don’t mind.

[andyandjulie]

Hi

Just a random thought. Is it possible the valve timing is a tooth out? I can remember reading something in an old copy of Car and Car Conversions along this line years ago. Not sure if this is even possible with this engine.

I doubt very much the timing chain has gone again in 6K miles.

Good luck

Andy

[xantia_v6]

There were several iterations of improvement of the THP timing gear. I think that the chain was improved by 2011, but maybe they had another go at the tensioners in 2012.

If the problem is just a hesitation, then I would be looking elsewhere, if your diagnostic tool can read live data, then I would be looking for uneven (across the cylinders) ignition dwell and timing, also fuel correction across the cylinders and general fuel and air trims at the point that the misfire occurs.