Ds3 Thp 150 Engine Noise

[djole]

Hello,

i just bought this week a Ds3 Thp 150 from 2011 with 16.000km on it.
I just heard a noise (knocking for 10 sec. stops and starts again)from my Engine which confuses me a little.
I hope someone can help me and tell me if this is normal sound of the Thp or do i have a problem?

http://www.youtube.com/watch?v=JtodkscruUk

[ZACK]

Knock Knock,

Who's There ?

Your THP that's about to go tick tick boom !

[lfcrule1972]

As Zack knows there have been some problems with THP 150 engines discussed at length on the forum in the past months...

You could start with the similar threads at the bottom of the page and then use the Search button at the top of the page for more threads on this... Do you have a warranty on the car you bought ? If so I'd be speaking to the dealer sharpish to have it looked at

Good luck

[Chris_Blue]

Its a late one if its suffers with knock, pinking (Pre-ignition of fuel) , timing chain issues. (Not seen one past March 2011 with these issues) What month is it of 2011?
Take it in pronto as its in warranty- but rear PCV delete would help if its that issue. Then catch can on other.
As said- lots other info on here bout it

ed: (Take it you have checked the oil- should be on max after 8 hrs, or engine cold)

[colganraz]

Its a late one if its suffers with knock, pinking (Pre-ignition of fuel) , timing chain issues. (Not seen one past March 2011 with these issues) What month is it of 2011?
Take it in pronto as its in warranty- but rear PCV delete would help if its that issue. Then catch can on other.
As said- lots other info on here bout it

ed: (Take it you have checked the oil- should be on max after 8 hrs, or engine cold)

how would a catch can or PCV delete remove a knocking noise from the engine :/ probably make matters worse if anything



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[Chris_Blue]

Removes suspended oil rather than it collecting, dropping back into the engine causing pre-ig, timing/ tensioner issues
AFAIK

" When shutting down, because of the vacuums within the engine and the layout of the rear PCV pipe, oil is left to collect in it, and when starting, assuming you drive easily until warm, is still sitting in the pipe because of the valvetronic valve system on the THP engines, which under light load only partially opens the valves.

Under harder acceleration, this oil in the pipe is sucked into the combustion chamber which has the effect of reducing the octane rating of the fuel (Think diesel in a petrol engine) and can cause detonation, which sounds like a tinkling, knocking, or loud clicking sound. (The knock sensor is frantically trying to compensate by adjusting the timing).

The noise can cause destruction of pistons, piston rings, and valves and shouldn't be ignored"

All THP 155s have a differently configured PCV pipework

One of the best threads I read on the defunct ds3club.eu site
Thanks to the contributor on that site.

[djole]

Thanks for your Reply,

well the car was produced 03.2011.

I bought it from citroen dealer so i have 1 Year warranty ill bring him on monday to them.

Ill tell you what happend.

[colganraz]

cheers for the lengthy reply chris, not convinced on that theory but i wouldnt argue against it as i couldnt say for certain.

over on 207.oc i have never heard of knock from PCV, and our cars have been around for alot more years/miles than ds3. only ever bad feedback from rear PCV delete, PCV is there for a reason otherwise it wouldnt have been designed, the drawback is the carbon build up on air intake valves which causes air restriction on the valves eventually

only unusual engine noises i have heard on these engines is from timing issues

djole, if your car is pre igniting as chris seems to think, run a tank of shell Vpower with the higher RON rating and see if the problem persists

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[Chris_Blue]

Yes djole- take it in a say your not happy

colganraz- yes, carbon build up on valves is also an issue- thats why Citroen sometime " Need to spray expensive spray" as cleaner

I feel there are better products on the market

PCV issue on earlier models (djole is a very late, early model) is well known. search button on here
And yes- a lot of engines (Like my 2 THP engines) did not need PCV delete- only need if these problems happen, Driving technique etc etc.

djole- if the car was first registered March 2011, it could have been built late 2010 (You need to find the build date)

[djole]

Hy,

yes Chris_Blue u are right its registered March 2011 but built November 2010.

Ill try a tank with higher Ron 100 or Vpower.

I have one more question: Whats does PCV stand for?

Thanks

[richy233]

Positive Crankcase Ventilation

[Chris_Blue]

djole- be interesting to see what the dealer Techs say
If it were out of warranty, I would say fit a catch can, delete the rear PCV pipe, and use a cleaner like BGK44
But I am certainly no expert.

[colganraz]

still not convinced on the PCV causing knock buy hey

PCV - pressure crankcase ventilation, it is there for a reason, to release pressure in the crankcase, surely the manufacturer wouldnt have added this if not needed? so why go block it off...

please please dont use a cleaner, seafoam etc might as well go pour your money down a drain

catch cans are generally poor aswell, the forge one is basically shiny shit, has no impact whatsoever, best ones are the filter ones but have no option to clean out

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[Gazski66]

still not convinced on the PCV causing knock buy hey

PCV - pressure crankcase ventilation, it is there for a reason, to release pressure in the crankcase, surely the manufacturer wouldnt have added this if not needed? so why go block it off...

please please dont use a cleaner, seafoam etc might as well go pour your money down a drain

catch cans are generally poor aswell, the forge one is basically shiny shit, has no impact whatsoever, best ones are the filter ones but have no option to clean out

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Colgan, are you a mechanic by trade?

[colganraz]

Colgan, are you a mechanic by trade?

no, a mechanical engineer with a keen interest in motor vehicle.. if you mean that in a "your not qualified to say so" kind of way, i am speaking from experience of having some knowledge of engines (although limited, more than many) and owning a THP engine, also speaking from experience of topics on our forum... our cars have used THP engine the very same as ds3 for almost 8 years now, there is many more years of experience and feedback from users who have had these engines upto alot higher mileage and age

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