THP engine breakage: Turbo + timing chain + power loss on acceleration + cold-start

[Dangerousfish]

Sorry to be dense, but can someone please explain what "superknock" is, what causes it, and what it does to the engine?

In simple terms it's due to fuel igniting in the cylinders earlier than it should do (pre-ignition) as well as this causing a carbon build up it also has the potential to blow the piston's (as it did in my case).

[szes30]

A Citroen and Peugeot specialist taught me this issue caused by not only the timing chain itself
but also the bolt fixing sprockets to camshaft and crankshaft.

And he also told me this problem happens even in 2011 production cars as well like mine

[monkeynuts]

A Citroen and Peugeot specialist taught me this issue caused by not only the timing chain itself
but also the bolt fixing sprockets to camshaft and crankshaft.

And he also told me this problem happens even in 2011 production cars as well like mine

The Timing wheels are not located with keyways (woodruff key)all the are is on a Taper I believe and the nut is then torqued up with a procedure .........now if the nut comes undone you loose your timing

Also the tensioner is hydraulic and relies on oil pressure to push it up against the chain to stop it flapping about sometimes the tensioner fails and the timing slips when this happands the Ecu retards the enging to safeguard it ...........Cuk a while back blamed it on incorrect oil from delivery ....................Bollocks !!!

My one both times used to go into limp mode and then out when the chain tightened this was with no fault logged in the system.So no fault no prob or so they say

[gillygilly]

Hi chaps,
first post alert!!!!
I have a ds3 1.6 thp sport I had a Viezu remap on it in 2013 and the engine blew in May this year. Citroen put a new one in ( without knowledge of the remap ) under warranty ( by 3 weeks, phew ). I had the remap put back on and 3 months later im experiencing problems again such as engine mgt light coming on going into limp mode, plugs sooting up, and a bit chuggy while idling. So ive had the remap taken off. Viezu say its not their remap causing the problem. So what is>?? Is this the common problem you have discussed about before??

Thanx

gilly

[Chris_Blue]

Hi Gilly- welcome to the Club. Take some time to search this forum- theres loads about this
Had a Viezu map on my 150 for 20k, didn't give me an issue
However, when the map was looked at by someone in the know, they had issues with the fuel/air mix being too rich, which may have caused issues over time
I took the map off and part exed the car

What is date of manufacture of your THP do you know? Understand it was first registered May 2011 (Mine was June 2011)

[Dangerousfish]

Hi chaps,
first post alert!!!!
I have a ds3 1.6 thp sport I had a Viezu remap on it in 2013 and the engine blew in May this year. Citroen put a new one in ( without knowledge of the remap ) under warranty ( by 3 weeks, phew ). I had the remap put back on and 3 months later im experiencing problems again such as engine mgt light coming on going into limp mode, plugs sooting up, and a bit chuggy while idling. So ive had the remap taken off. Viezu say its not their remap causing the problem. So what is>?? Is this the common problem you have discussed about before??

Thanx

gilly

Welcome to the forum Gilly! If you take the car to BCC in Bolton, they'll be more than familiar with the issue as they dealt with the first engine replacement on my 2010 and subsequently investigated faults with my second engine.

Out of interest, what are the last few characters of your reg?

This thread is going to be a good starting point for you:

http://www.ds3club.co.uk/showthread....THP-power-loss

[gillygilly]

wow, super quick replies guys thanx. The last 3 digits HFT. It was BCC that did the work/engine under warranty. I took the plugs out before it went to BCC and there was oil on them. They would not tell me what the codes were. They tell me that the new engines warranty ran out with the cars warranty in June 14, so no warranty. Viezu seem to think there is something wrong with the car but I want to have some idea what exacttly could be wrong before I go as they will want to charge me.

Thanx

Gilly

[Chris_Blue]

Would ask how much the costs to investigate are before you hand over your car
ie: Don't think they should charge you until they find the problem, and they say how much the repair is

There were a few people with issues running the Viezu map- but all I can say is I didn't get any for the time I had the car.
Wonder where Viezu gets their adamant opinion that its not their map (I am not saying it is their map)
But the earlier the THP, the more problems they seem to have had- especially if driven hard
How many miles yours done?

[Dangerousfish]

wow, super quick replies guys thanx. The last 3 digits HFT. It was BCC that did the work/engine under warranty. I took the plugs out before it went to BCC and there was oil on them. They would not tell me what the codes were. They tell me that the new engines warranty ran out with the cars warranty in June 14, so no warranty. Viezu seem to think there is something wrong with the car but I want to have some idea what exacttly could be wrong before I go as they will want to charge me.

Thanx

Gilly

Bummer on the warranty. Might be worthwhile looking into purchasing an extended warranty(if that's an option?) with Citroen or buying a third party one.

The thread I linked to discusses multiple faults that owners of the THP have had and some with the exact symptoms you reported (the same as what I suffered), so definitely worth a read when you have some time.

So far, theres fixes and workarounds:

Fixes
- Uprated pistons and a good deep clean of the engine Ragnarok took this route with his modified DS3R and so far hasn't suffered any major issues.

- Engine swap for the newer THP engine which so far doesn't seem to suffer the same issues.

Workaround's
- Walnut blasting. Find someone who has this magical tool that gives the engine a deep clean using walnut shells. SPTuning are a partner of the forum who can do this and offer discount to members on remaps and other services. I've been down there a couple of times and the tea service is fantastic!

- Oil-Catch can(s). The THP is known for filling up with sticky oil residue and gunk. Some members have found fitting a catch can or two to be beneficial and to catch a fair bit of vapour and occasionally oil which would otherwise sit and stir.

From the symptoms you've reported I'd suggest looking at a fix sooner rather than later. I'm a known pessemist but from experience, bills to repair this at it's worst can cost a fair bit.

Keep us updated with how you get on. If you need any more advice, I'm no doubt only round the corner so feel free to give me a shout.

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Gilly, I've copied your thread here: http://www.ds3club.co.uk/showthread....-advice-needed

You should hopefully get more views with people viewing new posts.