Xantia HDi smoking

Post by **DHallworth** » 27 Apr 2009, 15:13

Hi Guys,

About a month ago I bought my girl friend a Xantia HDi Exclusive.

The car is in good nick and has about 10k miles ago had a timing belt changed.

We were both leaving for work at the same time the other morning and I noticed when she started it there was a big cloud of black smoke that came out of it. I thought at the time it was a bit strange and thought it probably just needs a blast.

I had to change the rear box on it the other day as it broke away and I noticed that there was a lot of muck all under the back. As she'd driven it 20 miles before I did it I thought i'd give it a good blast to 5k rpm to clear it out and it put a HUGE cloud of black smoke from the exhaust, I let it idle again for around 30 seconds and did it again, and we got another huge cloud of smoke.

I noticed today when she pulled off with the car warm again that there is a constant bluey diesel type smoke coming out of the exhaust even when she's changing gear at around 2k rpm. It's also there when the car is idling, just a constant blue haze coming from the exhaust.

It doesn't feel that sluggish but I've never driven a 110 before, only a 90bhp 306. It occasionally on cold mornings or if it's been sitting for 24 hours or more sounds like it catches on 3 cylinders and literally 2 seconds after catches the 4th.

It's already had one bottle of injector cleaner in it when we got the car but it doesn't seem to have made much change.

Has anyone suffered anything similar? I've got a 306 HDi with 120k on it and it's as clean as a whistle, no smoke, not even when thrashed and it's on it's original injectors.

Any advice appreciated.

Regards

David.

AndersDK · Post by **AndersDK** » 27 Apr 2009, 15:55

I'd say the blue tint smoke is engine oil participating in the combustion.
Unburnt diesel produces black smoke.

I would start my investigation on the inlet side then, as there should be clear traces of oil in air ducts and intercooler from the turbo.
If this is a wet oily mess I would suspect the cold side turbo oil seal.
If there are no abnormal traces of engine oil it must be internal to the engine then.

The hot side turbo seal would leak oil directly into the exhaust, where the heat would make it evapourate immediately. This produces a white smoke.

Post by **CitroJim** » 27 Apr 2009, 16:38

I'd be inclinded to check the operation of the EGR valve. Sounds like it may be partially stuck open. I'm not exactly sure of how to disable it as I believe if you just do the normal trick of disconnecting the vacuum pipe to it, an error will be flagged in the ECU.

If not that, a Lexia session may reveal some thing as from the symptoms it soulnds like it may be running a bit retarded and paradoxically, this can cause blue smoke...

Post by **DHallworth** » 27 Apr 2009, 16:47

If it's anything like the 306 HDi was I unplugged the electrical connection going into the EGR and left it like that, nothing else was needed.

If I unplug it and it triggers the engine management light will it go out again if I plug it back in?

Anyone near Glasgow got a Lexia?

EDIT: Is ELIT the same as Lexia?

David.

citroenxm · Post by **citroenxm** » 27 Apr 2009, 18:32

David,

Elite is for cars up to 1993 I THINK, but im not certain..

There could well be a broken fire proof washer and plastic sealing seat in under the injector..

As any of the injectors got any "plastic" type deposits around the top of them???

Paul

DickieG · Post by **DickieG** » 27 Apr 2009, 20:02

DHallworth wrote:EDIT: Is ELIT the same as Lexia?

An ELIT is able to do similar things but how much will depend upon the date of the memory card within it. I believe they can go up to as late as 2004, but for instance the card in mine only does up to 1996.

citroenxm · Post by **citroenxm** » 27 Apr 2009, 20:23

Ahhhhh as I admitted, I was NOT sure at all, I thought the Lexia replaced the Elite...

Learning all the time

Paul

marsalek · Post by **marsalek** » 27 Apr 2009, 22:17

DHallworth wrote: If I unplug it and it triggers the engine management light will it go out again if I plug it back in?
David.

Hi David,
it depends on the firmware version of your ECU. Some Xantias do, some don't. I personally unplug the vacuum inlet to the EGR electrovalve and push some small bolt into the pipe to avoid entering dust into the vacuum pump.

If this solves the problem, I wouldn't replace anything. EGR is not a vital part of your Xantia

Karel

lolingram · Post by **lolingram** » 28 Apr 2009, 08:47

I'd be inclinded to check the operation of the EGR valve. Sounds like it may be partially stuck open. I'm not exactly sure of how to disable it as I believe if you just do the normal trick of disconnecting the vacuum pipe to it, an error will be flagged in the ECU.

No problem here Jim. My Xantia HDi 90 runs just fine with EGR disconnected - just the pump tube.

Post by **DHallworth** » 23 Jan 2011, 22:20

Well I'm going to revive this thread!

Cheryl has had the car for nearly 2 years now and has done 25k miles in it.

The car still smokes like buggery.

If your doing 70mph on the motorway at 2400rpm it looks clean behind in the mirror, if you change into 4th at 70mph it's doing circa 3000rpm and still appears clean behind you.

If you put your foot to the floor it puts a THICK cloud of black smoke out behind the car.

I've change quite a bit on the car in the 2 years we've had it but it doesn't seem to have made much difference.

It's been fully serviced 3 or 4 times.
Had the injectors changed with new washers and spacers
4 new glow plugs
New glow plug control box

I completely removed the EGR valve at the back of the engine as it was caked in oil. The metal tube that runs along the inlet at the back was full of lumps of hard black oily gunk. I cleaned it, put it back on and it's still smoking.

It doesn't use any oil and it's returning over 700 miles from a tank of Diesel. I've driven another HDi 110 recently and there's no noticeable difference in performance either.

Here's a video of the smoke in our workshop (it wasn't revved beyond 3k to do this!)

When I took the plastic pipe off the intercooler that runs under the gearbox there was a bit of oil in it but nothing that would suggest there's something seriously wrong.

Lexia doesn't pick anything up apart from a short circuit on a glow plug relay! That'll need looking into on another day though.

Anyone got any ideas?

David.

HDI · Post by **HDI** » 23 Jan 2011, 22:39

On an HDi fueling is obviously controlled by the ECU so something is causing the ECU to overfuel on acceleration. The MAF is responsible for the airflow signal to the ECU by which it adjust's fueling along with other factors like engine speed, TPS signal, ambient temp, coolant temp etc.

MAF's have a finite life, the one on mine had started to disintegrate and was causing inconsistent engine response. I suppose if it goes out of calibration it could cause inaccurate fueling.

Really the only way to diagnose this for sure is a Lexia.

Post by **myglaren** » 23 Jan 2011, 22:41

Very unusual for a PSA HDi to produce black smoke except on very rare occasions - like when booting it down the motorway after a lot of town driving they can kick out an impressive black cloud - so I have heard, never seen it on mine. I do occasionally get a cloud of grey smoke when it is starting (takes a while now) and when accelerating when it isn't warmed up (first couple of miles on a cold day).

Compared to the crap I see belching out of VAG, BMW, Ford and Vauxhall engines they are exceptionally clean.

How does yours fare in the emissions test at MOT time?

Post by **DHallworth** » 23 Jan 2011, 22:41

I've got a Lexia and it's only giving a fault about the glow plugs.

I changed the MAF sensor with one from my Peugeot 306 HDi and it made no difference to the smoking.

I'm wondering if it could be something to do with a dodgy remap in the past. I've got a Xantia HDi 110 SX here which runs beautifully so I'm wondering about copying the ECU map over to this car to see if it'll run ok.

Although there's no smoke at idle it stinks. It smells very rich so I'm also thinking of taking the inlet off incase it's all coked up and isn't allowing enough air into it.

David.

HDI · Post by **HDI** » 23 Jan 2011, 22:51

The other issue that can cause black smoke is inadequate air supply.
I'll assume the air filter has been checked. Another possible contender is a faulty turbo, either a sluggish due to bearing issues or choked with oil and carbon. Might be worth checking boost pressure.

dieselnutjob · Post by **dieselnutjob** » 23 Jan 2011, 23:01

the EGR valve might be stuck open a bit (or a lot)
if so then even disconnecting it from the ECU wouldn't help because it would be open even if the ECU isn't opening it
I would suggest putting a metal plate either between exhaust manifold and EGR, or between EGR and inlet manifold.
Basically you want a fake gasket with no hole in the middle to block the EGR system
A piece of sardine tin should do it.
That way no exhaust gas can get past it even if it's kippered.

Also make sure you are getting 1 bar of boost pressure from the turbo.