Unblocking a HDi exhaust NOW WITH Video!

Unread post by **citroenxm** » 20 Jun 2011, 15:10

Hi all..

Ive a HDi 110bhp Xantia in, Ive found the non functioning turbo cause, so know what I need, but the next challenge is a blocked exhaust..

Well, its not completely blocked as the engine does run with it attached but theres minimal comming out the exhaust!

What is gonna be the easyest way to clear it out?? I damm good HARD blast with full turbo boost down the road or Im I going to have to remove it ??

With the engine idleing if I cover the tail pipe and let the exhaust pressure build up and remove my hand I get an almightly black cloud... this doesn't happen on my every dayer... so Im looking for sugestions for "Emptying" it

Paul

DickieG · Unread post by **DickieG** » 20 Jun 2011, 16:06

Removing it is obviously the correct way but to save time you could try whacking it in strategic places with a hammer to dislodge the soot, especially if someone is blipping the accelerator at the same time.

I'd be careful about using the Italian tune-up method if its as bad as mentioned, I'd be concerned for the turbo both from a heat build-up point of view and the risk of back pressure as suffered by C5 2.2's.

Stempy · Unread post by **Stempy** » 20 Jun 2011, 17:59

In the old days of two stroke motorbikes we used to take the pipes off and set them alight

Deanxm · Unread post by **Deanxm** » 20 Jun 2011, 18:11

i would say this is whats killed the turbo, pull the cat of and beat the monolith out....................i mean take the old cat off and clean it out the best you can or buy a replacement Paul.

D

dieselnutjob · Unread post by **dieselnutjob** » 20 Jun 2011, 22:41

straight bits of pipe are £10 or so from Partco
cut the cat out and replace with straight pipe

Unread post by **citroenxm** » 20 Jun 2011, 22:44

Cheers guys..

From an interesting point tonight, I found some working Vac Solinoids and put them on the car and started it up ...

And rev it wouldn't do... the exhaust BELLOWED black and smelly like "Cooked" Fumes out the exhaust, Ive got a video, but my laptop is dying a slow death and will not talk to any USB device... so I cannot upload it...

So I guess its pipe off and replce, OR cu the cat out and fit a striaght pipe!

Thanks for confirming.. Getting somewhere at last with this late one!

Paul

steelcityuk · Unread post by **steelcityuk** » 21 Jun 2011, 13:48

My favoured method is to cut the exhaust so the cat can be smashed out. Watch out for turbo spikes and over boost errors though, I've never had a problem but it has been reported especially after a remap.

Steve.

Unread post by **citroenxm** » 21 Jun 2011, 22:53

Hi all..

I took a vid of the Hdi exhaust the other day:

Looks like this:

Paul

Unread post by **citroenxm** » 21 Jun 2011, 22:56

So thats full throttle, the restriction is sooooo bad you can hear the engine slow!! And yes she isn't reving freely, and Im just holding the throttle full!

Shes fine with the exhaust undone at the manifold!

Paul

Deanxm · Unread post by **Deanxm** » 21 Jun 2011, 23:08

Just being choked to death by the cat blockage, unless the silencers are rotten out and are filled with insulation thats dropped in and blocked the exhaust.

Amazes me how it managed to get so bad, no wonder the turbo was dead, must of cooked it alive.

D

Unread post by **citroenxm** » 21 Jun 2011, 23:10

Right, confirms confirms... yes there was a burnt smell.. Think Ill drop the whole lot off manifold to back box...

Paul

miked · Unread post by **miked** » 21 Jun 2011, 23:14

So do you think the cat is blocked?

If so. I 'unblocked' one on my old petrol xsara vtr with a metal pole and a lump hammer. It didn't pass the MOT afterwards and in hindsight I should have weighed in the cat and put the money towatds a replacement.

But a diesel doesn't need a cat, so depending on condition, either replace it with a new bit of pipe or smash the insides out of it.

Deanxm · Unread post by **Deanxm** » 21 Jun 2011, 23:14

looks like a nice car Paul, like the colour too.

D

Unread post by **citroenxm** » 21 Jun 2011, 23:17

She IS very nice, its maritious blue, SX HDi 110, with just 117k, new clutch 2k ago, and anew cam belt and water pump 3 k ago, receipts to proove too..

X plate 2000 model too...

Miked, it has to be a blocked cat, with the pipe dropped off I was getting full revs, and with lexia attached with live parameters, 1500 mb turbo boost pressure! Only after I tightend the exhaust back up she - well tried to die...

Paul

Deanxm · Unread post by **Deanxm** » 21 Jun 2011, 23:18

yours?