Black smoke

[Terranical]

My '94 T2 (non-intercooler) has always emitted a good puff of black smoke on start-up and when "blipping" the throttle, however it has now failed it's Spanish MOT on emissions.
I initially dropped a bottle of injector cleaner into an almost empty tank and gave it a good pasting for around 10 miles up and down a dual carriageway. When this failed to make any difference I tried a repeat performance, again to no avail.
I then bit the bullet and had a spare set of injectors rebuilt with new nozzles, and had them fitted (at a total cost of around £200), and now it's worse still.
The cloud of smoke is denser and it also smokes when I am accelerating, which it didn't before.
It definately appears to be unburnt fuel smoke, not engine oil (the level on the dipstick doesn't move).
Any ideas anyone?

 

[glen]

Diesel smoke problems

DIESEL SMOKE PROBLEMS

Black Smoke

This is due to a air to fuel ratio imbalance, either the fuel system is delivering too much fuel into the engine or there is not enough clean air (oxygen ) a few things to look for:

Faulty injectors (injectors need attention at about 100.000 to 120 000 miles)
Faulty injector pump
Dirty air cleaner
Turbocharger or intercooler faulty
Problems within cylinder head, valves clogged up due to faulty EGR (exhaust gas recycling unit)

White Smoke

Normally means that the fuel injected into the cylinder is not burning correctly. The smoke will burn your eyes.

Engine/pump timing out
Hole in fuel line leaking allowing Air in system
Fuel starvation to the pump causing the pumps timing not to operate correctly
Low engine compression
Water/petrol in the fuel

Blue Smoke

The engine is burning engine oil

Worn cylinders or piston rings
Faulty valves or valve stem seals
Engine over full with engine oil
Faulty injector pump/lift pump allowing engine oil to be mixed with the diesel


Glen

 

[Terranical]

DIESEL SMOKE PROBLEMS

Black Smoke

This is due to a air to fuel ratio imbalance, either the fuel system is delivering too much fuel into the engine or there is not enough clean air (oxygen ) a few things to look for:

Faulty injectors (injectors need attention at about 100.000 to 120 000 miles)
Faulty injector pump
Dirty air cleaner
Turbocharger or intercooler faulty
Problems within cylinder head, valves clogged up due to faulty EGR (exhaust gas recycling unit)

White Smoke

Normally means that the fuel injected into the cylinder is not burning correctly. The smoke will burn your eyes.

Engine/pump timing out
Hole in fuel line leaking allowing Air in system
Fuel starvation to the pump causing the pumps timing not to operate correctly
Low engine compression
Water/petrol in the fuel

Blue Smoke

The engine is burning engine oil

Worn cylinders or piston rings
Faulty valves or valve stem seals
Engine over full with engine oil
Faulty injector pump/lift pump allowing engine oil to be mixed with the diesel


Glen

Thanks for that Glen, can eliminate a few of those, it's definately black (as your hat) smoke. Had refurbished injectors fitted, not had a new air cleaner recently, but I did take it it out and tapped all the dust out, I then tried it for a couple of miles with the element out altogether, still loads of black smoke. No intercooler or egr so that won't be it.
That leaves the injector pump, the turbo and possibly a head problem.
It's not had a service for around 18,000 miles, so it's possible the valve clearances may need adjusting, but I don't know whether that would cause black smoke.
I must admit I'm out of ideas.

 

[supergnome]

Have you given it a good thrash up the M-way?
Change fuels, SVO etc. Mine always runs better after a long run at 70 to 80mph. David

 

[iain.s]

18,000 can you get hold of acetone 100% pure ? 100ml to 20 litres approx can help clean system :naughty and usually helps emmissions ,smoother more economic & more power

 

[solarman216]

Do not like the sound of "refurbished injectors fitted now it is worse" I would seriously question the quality of the new ones or correct nozzles fitted or maybe dirt was allowed into the new injectors on refitting, whatever it cannot be worse with good injectors, Rick

 

[iain.s]

I agree with the injectors whatever happens should be better , should go see person that fitted and get redone !

 

[96terrano]

What's you're air filter like, when I first got my terrano, it smoked badly, yhanged the air cylinder filter and removed airbox and fitted a k&n cured the smoke. Hope you get it sorted mate, are the spannish MOT striker then the uk version?

 

[mjpetersen]

I second the air filter suggestion. That would be my first thought, It is clear that it is over fueling, that is that there is too much fuel for the air available. Try to think of things that could cause that. blockage in air intake (bird's nest in intake pipes before filter--don't laugh I have seen it), turbo not doing its job, EGR valve not closing, or fuel pressure relief valve sticking (usually this results in under fueling especially at idle, but possible)--these are ideas that come to my mind and many of them are not hard to check out.

best of success,

Mike

 

[Terranical]

Thanks for all the suggestions guys, re the injectors Rick, they were refurbished by a Bosch specialist in the UK, who had all the details of the vehicle they were to be fitted to (he seemed to know what he was talking about, he knew that on my model all the injectors are the same). I have some reservations about the guy who fitted them here in Spain (English, and a retired mechanic). When he removed the old injectors, as well as the large copper washers that seal to the block, he found a set of smaller copper washers just below the nozzle itself. He said they shouldn't be there and binned them! Regarding the filter, I am going to replace that, just to eliminate it.
The Spanish aren't particularly stricter than the UK MOT people, they just seem to place importance on different things i.e. it will fail if it has a towbar that is not shown on the registration document, likewise if it has spotlights or any other extra lights. Basically a vehicle must have the spec it left the factory with, anything different such as raised body or larger wheels is an immediate fail, however, my handbrake will not hold the car on a steep hill, but they passed that!

 

[solarman216]

best injectors in the world will be useless if installed dirty, rest my case, Rick

 

[Terranical]

I am now thoroughly cofused regarding the heatshield washers below the injectors that my fitter binned when renewing the injectors, saying they weren't necessary.
I have checked the parts manual and no washer is shown below the nozzle, only the copper sealing washer and the leak off washer. I have also looked for a listing for a heatshield washer for an R20 engine on eBay and other sites, but can find nothing.
Can anyone give me a definitive answer as to whether these should be fitted or not - please?

 

[geoffdown]

I am now thoroughly cofused regarding the heatshield washers below the injectors that my fitter binned when renewing the injectors, saying they weren't necessary.
I have checked the parts manual and no washer is shown below the nozzle, only the copper sealing washer and the leak off washer. I have also looked for a listing for a heatshield washer for an R20 engine on eBay and other sites, but can find nothing.
Can anyone give me a definitive answer as to whether these should be fitted or not - please?

Mine had them fitted so I replaced them mine is a tdi :nenau