THP reliability

[Alexwheath]

Morning guys
I know this is a somewhat covered subject, I've searched Google and this forum for a few answers to questions I have but not had much joy.
So I'm looking at getting a DS3 probably a 2015 model with the 165 engine which I understand is revised.
Now I know the old ones suffer with coil packs HPFP and timing chain issues. I've had minis in the past and under stand the N14 engine 2008-2011 was a major player for these problems but mainly ironed out with the N18 released back end of 2011. Now mini obviously sharing a PSA engine to an extent how come DS3 still have issues post 2011 and my main question is do they have issues around 2014/2015 with regards to chains etc etc
Sorry if that's a bit mumble jumble haha
Thanks in advance!
Alex

[BenS]

The reason DS3s still have issues is that, although they share the same base engine block (Prince engine), they are put together with PSA parts, not BMW parts. The equivalent N14/18 engine is known as EP6DT for PSA, and is only probably about 50% the same parts.

As far as I'm aware, the 165 ironed out most of the creases of the early 150 (2010-13ish) including the timing chain, although it would be a good idea to keep an eye on it at MOTs and services, also checking cam alignment at the same time. You will still get valve carbonisation as this is an inherent characteristic of the engines, both in PSA and the BMW Mini. I'm sure you came across walnut blasting in your searches - this will 100% remove the deposits, necessary after 20-30k miles depending on severity of buildup.

Treat it with good fuel (i.e. not supermarket crap) and keep on top of servicing and maintenance, and you will probably be just fine. Any worries and there's a wealth of knowledge here for pretty much any fault related to the THP.

[Alexwheath]

The reason DS3s still have issues is that, although they share the same base engine block (Prince engine), they are put together with PSA parts, not BMW parts. The equivalent N14/18 engine is known as EP6DT for PSA, and is only probably about 50% the same parts.

As far as I'm aware, the 165 ironed out most of the creases of the early 150 (2010-13ish) including the timing chain, although it would be a good idea to keep an eye on it at MOTs and services, also checking cam alignment at the same time. You will still get valve carbonisation as this is an inherent characteristic of the engines, both in PSA and the BMW Mini. I'm sure you came across walnut blasting in your searches - this will 100% remove the deposits, necessary after 20-30k miles depending on severity of buildup.

Treat it with good fuel (i.e. not supermarket crap) and keep on top of servicing and maintenance, and you will probably be just fine. Any worries and there's a wealth of knowledge here for pretty much any fault related to the THP.

Ben thanks for such a detailed reply,
Yeah I had my mini walnut blasted and only run the cars I own on BP/shell
Great stuff be interesting to see if anyone has had any issues, problem I find on forums is people only report faults in sure many out there have been fine

[eddiemunster]

Although not strictly related to the THP, but, you only have to change one part in an otherwise reliable engine and you can affect reliability dramatically: for example, in the old K series engines, famed for head gasket failure, it was all down to Rover changing the dowling rods to plastic, which over time would warp and cause head failure. I have an R56 and a DS3, I can see "cost savings" almost every job that I do on them both.

[BenS]

^^^ Hit the nail on the head there. A very good explanation for the BMW/PSA differences in the THP.

[Czar]

The reason DS3s still have issues is that, although they share the same base engine block (Prince engine), they are put together with PSA parts, not BMW parts. The equivalent N14/18 engine is known as EP6DT for PSA, and is only probably about 50% the same parts.

As far as I'm aware, the 165 ironed out most of the creases of the early 150 (2010-13ish) including the timing chain, although it would be a good idea to keep an eye on it at MOTs and services, also checking cam alignment at the same time. You will still get valve carbonisation as this is an inherent characteristic of the engines, both in PSA and the BMW Mini. I'm sure you came across walnut blasting in your searches - this will 100% remove the deposits, necessary after 20-30k miles depending on severity of buildup.

Treat it with good fuel (i.e. not supermarket crap) and keep on top of servicing and maintenance, and you will probably be just fine. Any worries and there's a wealth of knowledge here for pretty much any fault related to the THP.

^^^ Hit the nail on the head there. A very good explanation for the BMW/PSA differences in the THP.

There appears to be some confusion regarding the prince engine, the PSA (Peugeot, Citroen) THP variant, and the BMW MINI THP variant, lets put this confusion straight, the PSA engine commonly referred to as the THP, as fitted to various models within the Peugeot, Citroen and BMW MINI vehicles, share the same common components, the engine cylinder block was a new updated design of the old Peugeot TU engine block, the THP cylinder head and all cylinder head components are a BMW design, exclusively, the joint efforts between PSA and BMW resulted in what is commonly referred to as the THP, whether the THP engine was fit to a Peugeot, Citroen or BMW MINI, the two variants of the THP, single vanos or the later double vanos with VVT lift, still share all common components, not a mix and match variation of PSA parts for the French variants or BMW parts for the German variants (MINI) one common platform between Peugeot, Citroen and BMW MINI.

[BenS]

There appears to be some confusion regarding the prince engine, the PSA (Peugeot, Citroen) THP variant, and the BMW MINI THP variant, lets put this confusion straight, the PSA engine commonly referred to as the THP, as fitted to various models within the Peugeot, Citroen and BMW MINI vehicles, share the same common components, the engine cylinder block was a new updated design of the old Peugeot TU engine block, the THP cylinder head and all cylinder head components are a BMW design, exclusively, the joint efforts between PSA and BMW resulted in what is commonly referred to as the THP, whether the THP engine was fit to a Peugeot, Citroen or BMW MINI, the two variants of the THP, single vanos or the later double vanos with VVT, still share all common components, not a mix and match variation of PSA parts for the French variants or BMW parts for the German variants (MINI) one common platform between Peugeot, Citroen and BMW MINI.

Really? I obviously didn't know that. Any reason why the DS3 seems to have a lot of tales of woe from owners, do Mini owners sometimes see the same things and just turn to the internet less? I've always been given the impression by others that the Minis with the THP engine didn't have many of the common problems we see here like timing chain, HPFP, and in extreme cases piston cracking/shattering. Are BMW more helpful than Citroen in resolving any such issues then, so there's less people searching for forum help?

Just trying to understand why it seems people praise the Cooper S while there's a lot of stigma about the petrol DSports (and especially the DS3R) if they are, in essence, the same?

[Dangerousfish]

Really? I obviously didn't know that. Any reason why the DS3 seems to have a lot of tales of woe from owners, do Mini owners sometimes see the same things and just turn to the internet less? I've always been given the impression by others that the Minis with the THP engine didn't have many of the common problems we see here like timing chain, HPFP, and in extreme cases piston cracking/shattering. Are BMW more helpful than Citroen in resolving any such issues then, so there's less people searching for forum help?

A quick google for "Mini cooper hesitation" reveals similar results to that seen when searching for results related to the DS3.

[BenS]

A quick google for "Mini cooper hesitation" reveals similar results to that seen when searching for results related to the DS3.

Hmm yeah a lot of people noting sluggishness and almost nobody actually giving answers! Gotta hand it to our resident experts here for knowing their stuff. Still not sure how I've been given the impression that the Minis didn't run into issues other than the carbon. Just read they did a recall for timing chains too, did the DS3 get a recall for this?

The best response I saw was a quote from this forum mentioning the most knowledgeable person in the world regarding the THP engine hanging out here. Something makes me think this was aimed at you Czar?...

[Dangerousfish]

Hmm yeah a lot of people noting sluggishness and almost nobody actually giving answers! Gotta hand it to our resident experts here for knowing their stuff. Still not sure how I've been given the impression that the Minis didn't run into issues other than the carbon. Just read they did a recall for timing chains too, did the DS3 get a recall for this?

The best response I saw was a quote from this forum mentioning the most knowledgeable person in the world regarding the THP engine hanging out here. Something makes me think this was aimed at you Czar?...

Funnily enough, when I had my THP I stumbled across one of Czar's posts on the mini forums too ^_^

[Czar]

Really? I obviously didn't know that. Any reason why the DS3 seems to have a lot of tales of woe from owners, do Mini owners sometimes see the same things and just turn to the internet less? I've always been given the impression by others that the Minis with the THP engine didn't have many of the common problems we see here like timing chain, HPFP, and in extreme cases piston cracking/shattering. Are BMW more helpful than Citroen in resolving any such issues then, so there's less people searching for forum help?

Just trying to understand why it seems people praise the Cooper S while there's a lot of stigma about the petrol DSports (and especially the DS3R) if they are, in essence, the same?

You learn something new every day, the BMW MINI THP engines, do indeed suffer from the same issues, timing chain, HPFP, and on rare occasions, the No3 piston failure, why do Citroen suffer more, two reasons, BMW MINI, were the very first to identify the engine issues, release superseded components to fix the known issues, whilst simultaneously designing the new cylinder head, for the second THP engine variation with dual Vanos VVT lift, this cylinder head was a rethink of the cylinder head already in running production as found in the BMW MINI cooper models (N12 engine)

BMW MINI are indeed a great deal more helpful with customer service, and fault finding, furthermore the second point, the ECU mapping control in the Citroen is very problematic, which is why the Citroen suffers more than the BMW MINI, the ECU mapping in the BMW MINI is much more refined when it comes to the known issues, especially the controlling of combustion heat, which is the downfall of piston No3.