Diesel, 1.9dci, spitting black smoke, renault laguna

grantk2

hey,

my renault laguna 2003 1.9dci is spitting black smoke from the exhaust every time i rev high. if i hit 2500 revs in 2nd or 3rd gear the cloud of smoke is unreal.. i hit 3000 revs in 4th and it was seriously bad.. im told it spits smoke when i take off in first even..

mechanic had a look and cleaned out the build up of carbon with brake cleaner and ran a litre of cleaner through it.. but it was only a temporary fix..

anyone have the same problem, there are plenty of lagunas on the road, (even though renaults have such a bad name!)

oh yeh, it has 174k miles on the clock, but runs great other than the smoke..

any ideas..

CJhaughey

Have you tried fitting a new air filter?
Maybe the injectors need overhauling/replacing?

grantk2

yeh air filter was replaced, its had a full service and the mechanic never mentioned anything about the injectors..

i hear its expensive to replace.

im not losing any power though..

i dont suppose it'll pass an nct with that coming from the exhaust!

what exactly did he clean with brake cleaner??

Alun

One suggestion from the garage I'm taking my Focus C-MAX TDCi to on Monday (see my recent thread on failing my NCT on smoke) is a clogged up EGR valve. From a bit of Googling, it would appear that brake cleaner is one proposed cleaning fluid for this .. maybe that's it?

could be a few things
EGR
Turbo
ECU
Injectors
Air intake manifold clogged(does happen on diesels with EGR)
not up on the lagunas so dunno what else to suggest, you dont always notice power loss when a turbo or injectors first go bad, takes very little to make a modern high pressure diesel smokey

its black smoke isnt it?
not blue or grey/whitish smoke?

what about the coil packs ?

reilig

grantk2 wrote: »

hey,



oh yeh, it has 174k miles on the clock, but runs great other than the smoke..

That's your problem, most cars with over 150k on the clock will smoke a lot.
It doesn't mean that your engine is going to blow or anything.
It just means that it will be harder to get it through the nct, but there's 2 things that you can do to make sure it passes - bring it to a diesel mechanic who has an emissions tester before the nct and get him to tune it down before the test (he can tune it up after the test to make sure you have the same power. Secondly, try running a gallon of petrol through a full tank of diesel for 3 or 4 tanks before the test. It will get rid of a lot of smoke.

As for stopping the smoke altogether, you can't unless you rebuild the engine.

Regards

Dan

Alun

Deleted User wrote: »

what about the coil packs ?

On a diesel?

CJhaughey

Deleted User wrote: »

what about the coil packs ?

This is the new Multifuel Renault engine right?

grantk2

its black smoke alright...

it just googled EGR valve and it says "You'll know if your EGR valve is stuck or malfunctioning because your car will experience symptoms like rough idle "

i doesnt always idle cleanly at 900rpm. its up and down at 900 but not always constant...

maybe this is the problem..

big job to get replaced??


i've tried a gallon of petrol in the tank and he sorts it out temporarily, ive been told its good to do every 6 months but to overdo it can damage the injectors..

the DCI lagunas have some sort of diesel coil pack that can go on them

But sounds now likes its the EGR.

snowman707

grantk2 wrote: »

i've tried a gallon of petrol in the tank and he sorts it out temporarily, ive been told its good to do every 6 months but to overdo it can damage the injectors..

worse than that I'm afraid petrol will f**k up your injector pump big time

I am always amused at the comments & solutions offered on this board from people that literally know sfa what they are talking about .

take your car to a realible mechanic, it will be cheaper in the long run.

reilig

snowman707 wrote: »

worse than that I'm afraid petrol will f**k up your injector pump big time

I am always amused at the comments & solutions offered on this board from people that literally know sfa what they are talking about .

Sorry to ruin your buzz, but if you read renault or VW manuals they will tell you that it is perfectly acceptable to run your diesel car on up to 20% petrol mix without any affect on your engine.

Water will ruin your diesel pump, most other combustable fuels won't - sure hell if your engine isn't common rail you could burn vegetable oil in it and I have even seen a 1991 VW Jetta run on waste engine oil.
I've worked in enough garages to see em all

peasant

reilig wrote: »

Sorry to ruin your buzz, but if you read renault or VW manuals they will tell you that it is perfectly acceptable to run your diesel car on up to 20% petrol mix without any affect on your engine.

I would like to see a copy of the manual where it says that... and don't produce one from 1960 !

On modern high pressure common rail / Pumpe-Duese engines mixing petrol into the diesel is a sure fire way to ruin your injection pump ...terminally, as these pumps rely on the lubricating properties of diesel to keep working.

Petrol is a detergent, washes away the lubricating film and causes these pums to wear heavily and eventually seize altogether.

snowman707

reilig wrote: »

Sorry to ruin your buzz, but if you read renault or VW manuals they will tell you that it is perfectly acceptable to run your diesel car on up to 20% petrol mix without any affect on your engine.

Water will ruin your diesel pump, most other combustable fuels won't - sure hell if your engine isn't common rail you could burn vegetable oil in it and I have even seen a 1991 VW Jetta run on waste engine oil.
I've worked in enough garages to see em all

Well if you had read the OP you would see there is a problem that petrol will not cure, I am drivng diesel engines 7 days a week for over 30 years & i have a fair idea of what is the problem, however I am not a mechanic & wouldnt issue any advise here, but I think that adding petrol will actually make this matter much worse.

" I've worked in enough garages to see em all "

Wonder why you move around so much ????? A garage tends to hold on to a good mechanic !!!!!!!!

JHMEG

OP, if you want a proper diagnosis bring it to a proper mechanic.

There are no mechanics here, and it shows, as there are some lunatic suggestions.

I would tend to say it's cos of its age and cos it's diesel. It's probably burning a bit of oil too? But again, I'm not a mechanic.

monster1

Sounds like the turbo. Turbo seals maybe?

peasant

Too much black smoke (not blue, not white, but black) on a diesel is a sign of too much fuel being burned/ fuel being burned incompletely.

This could have several reasons: not enough air (dirty filter, tired turbo, buggered sensor, wrongly set ECU), too much fuel being injected ( again several sensors, ECU and fuel pump), or leaking/misfiring injectors themselves.

Only a properly equipped mechanic will be able to tell you what it really is (could be combination of several factors as well)

The only thing you can check for yourself is the air filter ...and that's it then.

Worst case scenario is that a leaking injector actually fries your engine as surplus fuel is burned at inappropriate times and damages your cylinder head and/or the top of the piston ...so you want to get this looked at and fixed before this happens

reilig

snowman707 wrote: »

Well if you had read the OP you would see there is a problem that petrol will not cure, I am drivng diesel engines 7 days a week for over 30 years & i have a fair idea of what is the problem, however I am not a mechanic & wouldnt issue any advise here, but I think that adding petrol will actually make this matter much worse.

" I've worked in enough garages to see em all "

Wonder why you move around so much ????? A garage tends to hold on to a good mechanic !!!!!!!!

I thought that this was a forum about a Laguna spitting black smoke, not a forum for having a go at the contributors. I never even said that I was a mechanic, so what gives you the right to suggest that I am not good at my job when you don't even know what i do.
Cop on, you don't need to have a go at me or anyone else on this forum just so that you can make a point, its not a competition.

On a further note, I have the manual from our 04 Passatt which does state that if you put petrol into your diesel engine by mistake, it is safe to run it with up to a 20% mix without damaging the injectors or fuel pump.

I'm looking for someone with a scanner, and i will scan in the page for y'all to have a look at.

Finally, I never suggested that anyone should constantly run their car on a pertol/diesel mix. If you go back to my original post, I suggested that a mix of a gallon of petrol through a tank of diesel would help the car to pass the emissions test in the NCT. This is a well know fact, any mechanic who has experience of preparing cars for NCT will confirm this.

snowman707

reilig wrote: »

Finally, I never suggested that anyone should constantly run their car on a pertol/diesel mix. If you go back to my original post, I suggested that a mix of a gallon of petrol through a tank of diesel would help the car to pass the emissions test in the NCT. This is a well know fact, any mechanic who has experience of preparing cars for NCT will confirm this.

You suggested

"try running a gallon of petrol through a full tank of diesel for 3 or 4 tanks before the test. It will get rid of a lot of smoke."


4 tanks is about 2K miles, driving an engine on a D/P mix for that distance could do a lot of serious damage, what might cost a couple of hundred euro now could run into thousands on your advise. That engine with a little maintance now could be good for another 100K miles, on your advise I think the op would be lucky to get 5k .

I'm not having a go any one but any good mechanic worth his salt will tell you that unleaded petrol is lethal for modern day diesel injection systems.

As pointed out without a proper diagnosis it is impossible to tell the op what to do, leave it to someone that knows what they are talking about, & what they are doing.

BTW I have a car with 195K miles & a jeep with 250K kms both engines are un touched & no emissions problems

don't put yourself out looking for a scanner . I'm not interested, being on the road too long for hear say,

reilig

snowman707 wrote: »

I'm not having a go any one but any good mechanic worth his salt will tell you that unleaded petrol is lethal for modern day diesel injection systems.

QUOTE]

They won't, and I know that they won't because I have trained in this area, that's the reason why I have been in a lot of garages -I work rebuilding diesel injector systems and pumps - mainly bosch, stanadyne, zexel, lucas or delphi, denso or yanmar. If you ever got a diesel rebuild in the midlands, it probably passed through our engineering workshop. Maybe I'm not worth my salt and maybe I'm a bad mechanic (in fact I'm not one at all) or maybe I've been in an awful lot of garages around diagnsing, servicing, removing and replacing injectors and fuel pumps, but I do know that a gallon of petrol in a full tank of diesel will not damage the pump or injectors.

soundsrite

Deleted User wrote: »

its black smoke isnt it?
not blue or grey/whitish smoke?

what about the coil packs ?

dci engines dont have coil packs ......