Stage one remap, intermittent hesitation on acceleration & intermittent rough idle

[Bradato]

Right, this is a cry for help 😂 The cars mods so far include; Air intake kit, non-resonated back box.

My ds3 thp 155 has had a remap from a local remap specialist in Cardiff (they've never had a bad review and I've spoken to numerous people who have had a remap from the company and they've never had any problems, all in all a good place to go apparently), it's been remapped to approximately 185-190bhp (stage one). However, since the remap I've been having issues, this includes intermittent hesitation on acceleration & intermittent extremely rough idle, to start with, I changed the spark plugs which stopped the rough idling but the hesitation was rife. After reading numerous forums and getting a huge range of ideas from people with similar issues I decided to try and start with the little things, which included; engine oil and filter change, coil pack change (uprated), and I also used the Seafoam intake spray in case there was a carbon build up in the engine. I've even taken the car back to the remap specialists who tried removing the map, modifying the map, and then putting it back on, which seemed to work for a while, but now the problem is creeping back in now.
I was wondering if it may be something that I'm simply missing or if the problem is easily fixable. Or is it better off that I remove the map and see if the problem dissapears.
My brain is just shot now and I'm completely lost 😂 Any ideas?

[mjogreen]

Does sound like carbon build up, and as far as I remember seafoam and that other stuff doesn't touch it. Get a endoscope camera and pop that badboy through your intake see if it's all built up, then get booked in with Jamie at SP Tuning for a walnut blasting!

[Bradato]

It did feel a lot better after the seafoam, however I could tell that it wasn't perfect, thanks, I think that'll be the next step then, however, it's a bit strange for a car with only 40k on the clock isn't it?

[BenS]

it's a bit strange for a car with only 40k on the clock isn't it?

Haha you wish! This can happen as early as 15k and usually rears its ugly head around 25k. Yours will be dire at 40k!!

[Dangerousfish]

Hesitation can also be caused by a faulty fuel pump. Have a look at that too if it's going in to be checked.

[Bradato]

Really? Holy shit, is that in general or on the THP engine in particular? And if the fuel pump was fault it'd be constant rather than intermittent wouldn't it? However, i will have a check, any issues possible the way this car is going ��

[BenS]

The THP (or Prince engine) is especially prone to the buildup compared to other direct injection petrol engines. Pugs and Citroens are a bit worse than the Minis using the Prince engine though, since Mini use a lot of BMW parts and engineering rather than PSA parts.

[Chris_Blue]

when i had my remap with James on my 155, on which there was never an issue, I'm sure he told me he had isolated some glitch he had found on the OEM map, which had needed mapping out
Best suggest that to Jamie see what he says.

[Eagle]

I had a similar problem (also had a remap and a few other bits that increased bhp to around 215bhp)
I was feeling this hesitation as well on acceleration
The fault in my case was the chain tensioner after i replaced it the problem was solved