Clio dCi 65 - Lots of black smoke and no power

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Sat 1 Jan 2011 08:56
Clio dCi 65 - Lots of black smoke and no power - StanTheMan78

Hi, while driving normally the other day I got a sudden loss of power and lots of black smoke. I managed to get it home and took apart whole induction system but found nothing wrong except a couple of worn rubber sleeves which I replaced, along with a couple of jubilee clips which were not really up to standard. I reassembled the whole thing but the problem is exactly as it was.

Now, below are a few things I need to get straight:

* The EGR system is bypassed and blanked out, so it cannot be a dirty EGR valve as I removed it completely and blanked the whole thing out with core plugs. This has been working fine for months now.

* The engine is de-catted (no catalyzer)

*The turbo has been completely reconditioned by a professional (the only manufacturer's franchise in my country) less than 5k miles ago and has no play whatsoever in the shaft, so it's very unlikely it's got to do with the turbo. Also, if the turbo shaft had snapped it would not be delivering the required boost so the boost sensor would prevent the injectors from delivering the excess fuel which is producing all that black smoke.

* No engine light has come on.

Can you kindly advise?

Mnay thanks in advance and Happy New Year!

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Sat 1 Jan 2011 10:46
Clio dCi 65 - Lots of black smoke and no power - Peter.N.

I am not familier with your particular car but as a general principle black smoke is caused by incomplete combustion i.e insufficient air. Can you disconnect the air intake pipe at the manifold? if you can, try the effect of running the engine without it, if OK you have an obstruction in the air supply. The only other problem I know of is incorrect injection timing but to produce large quantities of black smoke it would probably be so far out it wouldn't run, unlikely anyway being electronically controlled.

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Sat 1 Jan 2011 11:19
Clio dCi 65 - Lots of black smoke and no power - Collos25

Cam belt slipped or pump faulty ,I would check the timing first and then the MAF sensor.

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Sat 1 Jan 2011 22:27
Clio dCi 65 - Lots of black smoke and no power - StanTheMan78

* Induction pipe obstruction - impossible since I have just took apart everything on that side

* MAF sensor - even in neutral with no load there is lots of black smoke from like 2000 rpm onwards so I don't think it's that

* Faulty delivery pump - one of my biggest suspects at first but ruled it out temporarily since it starts first time without any problems

* Slipped timing belt causing lost sync between injection and valve timing - didn't think of that but now that you reminded me sounds like a primary suspect...especially since from like 1500 rpm I hear a metallic clunking sound...just like a valve slightly striking a piston.

Timing belt is not due for another 20k kms though but it can snap practically anytime.

Two thumbs up for the idea...many thanks :)

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