[Stratagem72]

Hi there,

First post on the forum. 

Recently bought a 2007 fd slx.  Was told by someone driving behind me it was puffing out black smoke when I was putting foot down (not a huge amount).  Had it checked and they said my turbo was on the way out (impeller not spinning freely).  So, I had the turbo replaced.  A couple of grand later its still puffing out the black smoke. 

Also, when changing gears 1, 2 and 3, its a bit sluggish and then all of a sudden it will get a burst of power (its at this point the black smoke puffs out).  It has been suggested to me it might be dirty fuel injectors or injector seals??

I'd be grateful if anyone could shed any light on this as I'm not sure whether or not to spend too much more on it.   

[Phil №❶]

Black smoke is unburned Diesel fuel. Usually caused by dirty injectors and incorrect air / fuel ratio. There can be many causes for this as mentioned, fuel quality, contaminants, computer irregularities and the injectors themselves.

As the car is 07 model, it has most likely done a fair distance, so it would be expected that some replacements are due.

Surprised about the turbo, usually whining noise is the tell tale failure sign, not smoke. Under heavy load there can be smoke emitted, so perhaps drive a little more sedately as well.

If the impeller was not spinning freely it is usually caused by driving at high speed and stopping the engine without letting the turbo cool properly. At highway speeds, it is best to give the turbo a few minutes of suburban speed before switching off as the oil can cook on the shaft of the impeller causing deposits to build up and cause friction.

Use only full synthetic oil and the correct type and grade.

[Dazzler]

Welcome, hope the turbo really did need replacing! Shame you didn't find us earlier. A small amount of black smoke isn't too much of a concern in my opinion. As usual Phil has made some valid points. ☺

[Stratagem72]

Thanks for the replies.  Some good info there.

They showed me the turbo they took out and it definitely wasn't spinning freely and there was some give in the central shaft so I guess it did need replacing.  I am a bit disappointed it didn't solve the problem though. 

It's done 172000 klms which was a little higher than I would have liked, but the purchase price was pretty good.

Would it be expensive to have the injectors replaced? Is there perhaps a cleaning procedure that can be done?  I'm hesitant to send it to the Hyundai dealership as they charge upwards of $400 just to look at it 

[Phil №❶]

As it is out of warranty, I would seek the opinion of a reputable diesel workshop. For that distance, the injectors should still be ok, but may require cleaning, or it could be a control problem in the electrics. Maybe not too expensive to fix.

[crayman]

Modern diesel bears little resemblance to diesels of old, so unfortunately you really have no other option than to have it professionally checked.
There's simply too many variables, any of which would cause black smoke.
The milage is way small to be replacing items such as the turbo but then I don't even know what CHRA these things run, are they ball or bush bearing???
My old 32 would have to be one of the most complicated cars built for its day and I have no problems owning/maintaining it, but if you gifted me a modern CRD it would be on-sold as fast as it would go.

[beerman]

It really depends on the black smoke.

If you put your foot down in any diesel you will see the unburnt stuff go out the pipe.  Follow a Territory or Landrover and see what I mean (or look at the back of the car in winter).

My FD would blow a little smoke when I gave it a little bit....

[Stratagem72]

Yes I've seen this on other cars.  I think there may be some issue there though as there is some sluggishness in the low gears and a sudden burst of power.

When I can I will get some efi diagnostics done.

[Stratagem72]

Ok,  I've had diagnosis done,  throttle actuator was found disconnected which could have been causing the black smoke. Fuel injectors tested ok.

There's still some power lag which could be power loss due to use of air conditioner.

Ive been instructed to give it a good run to blow out any soot build up and report back.

Apparently the throttle actuator is commonly left off when oil filter is changed.

Does this sound reasonable?

[MetalDan]

The burst of power wouldn't be the turbo kicking in?

[Stratagem72]

It very well could be but I doubt that the way it's working would be normal as you virtually get no power when you want it and all of a sudden it kicks in about 5 seconds after you need it

[Stratagem72]

Further to this issue,  the car came up with an engine emissions warning.  It's going back in next week to have the egr removed and cleaned which I'm hoping was the root cause of the initial problem.

[Stratagem72]

Egr has been removed and cleaned,  power issue has improved but still the black smoke.  The mechanics have said the turbo is not spinning freely (again) and there may be some other issues that could cost several thousand dollars to fix.  Not happy.

[Phil №❶]

How much black smoke. All Diesel's are capable of producing black smoke under varying conditions. Don't ev the motor, just drive it.

[Stratagem72]

It puffs out enough to be slightly embarrassed pretty much each gear change from 1, 2 and 3

[Phil №❶]

I see your car is a 2007 model, given that it's now 2016, 8-9 yeas of use has probably had an effect on the injectors. A good cleaning using an injector cleaner regularly may enable some improvement over time. To have them removed and tested is an expensive exercise.

BTW I have observed much later models of car, not Hyundai's, chugging out black smoke under load climbing our local hills.

[Stratagem72]

Phew!  Thanks for that..... Any recommendations for a good injector cleaner to try?

[Phil №❶]

Not from me, hopefully other members will be able to advise. maybe @cruiserfied will know

[sundiz]

Many have said good things about Forte fuel additive products. I think they have injection cleaner in their product line. They may be hard to find, but here Skoda dealers make those treatments, or at least they did. It would be crazy to pay extra for that mechanic pours the additive in your fuel tank, so it would be better if you could get get your hands on the actual product. Ebay maybe?

I've used Redline RL-2 now for few years. It says it cleans the injectors and lucricates the fuel pump. I use it mainy because the winter/arctic diesel have been said to have slightly worse lubricating than summer one. In older diesels you can hear the difference when adding this stuff. Engine/pump runs smoother. Also my dads old diesel merc with ~360 000km got really good "smoke values" in the mot last time after adding RL-2. It costs ~20€ and at least in here you can get it from almost every car related shops. Also the bottle will last probably a year or two: In quick cleaning the bottle is for 400 litres of diesel. For everyday use the bottle is for 1100 litres of diesel. The bottle is 443ml.

[Phil №❶]

Where are you located @Stratagem72

[Stratagem72]

Nsw Australia 

That redline gear looks like it might be worth a try. Cheers

[cruiserfied]

Not from me, hopefully other members will be able to advise. maybe @cruiserfied will know

I recommend not using any fuel cleaning treatments in Hyundai Diesels. Even more on older models.

[sundiz]

I recommend not using any fuel cleaning treatments in Hyundai Diesels. Even more on older models.

Have you seen them causing issues with the car?  If so what had happened?

Here the dealer recommended fuel treatment for me. But engine flush should not be done if the engine has lot of km's. That may loose large pieces of carbon and cause issues.

[Dazzler]

Not from me, hopefully other members will be able to advise. maybe @cruiserfied will know

I recommend not using any fuel cleaning treatments in Hyundai Diesels. Even more on older models.

Hi Tim, not even in this situation??

[elantraelite]

I'd get your injectors bench tested before replacing them as they are very expensive.

I had mine tested at 140,000km and found they were working 100% within their ranges and passed all 5 Bosch tests on their equipment.

[rustynutz]

Not from me, hopefully other members will be able to advise. maybe @cruiserfied will know

I recommend not using any fuel cleaning treatments in Hyundai Diesels. Even more on older models.

Tim, I find your comment interesting as my local Hyundai dealer used to add a cleaner as part of my i30's service...

Is there any particular reason you don't recommend them? 

[cruiserfied]

I just dont think its healthy to collect all the buildup in the fuel systen and then send it through the fine tolerance high pressure pump and injectors. But thats just my opinion.

[Phil №❶]

So what's the best remedy for eliminating smoke production for this owner. Given the age of the vehicle, is a mechanical inspection rather than a simple additive the way to go. Surely soot build up can occur in any Diesel engine and I wouldn't be too keen to be paying for inspecting injectors too often.

[nzenigma]

It very well could be but I doubt that the way it's working would be normal as you virtually get no power when you want it and all of a sudden it kicks in about 5 seconds after you need it

Hi Stratagem,
 From what Ive read so far, your mechanics are looking at the smoke issue but ignoring the turbo lag.
If you are waiting "5 seconds" for a boost it must be a real horrible drive. My guess is that  the smoke and turbo lag are the same problem.
It may be a simple as this: You will see a fine rubber tube running from the pneumatic controller on the turbo down to the front of the motor. Here it meets a solenoid and several more rubber tubes. Check the rubber hoses for cracking, a small ( but not very obvious) leak can cause a 'flat spot' upon acceleration, a large break will result in no turbo operation at all.
I have also found one of the plastic inlets on the solenoid partly fractured due to a rough 'mechanic'. Missed it at first because of its position and small size.
Good luck.