Terraclean intake manifold de-coking

[fattail95]

Afternoon guys,

After having owned the car for nearly a year now, I could no longer put off cleaning the filthy intake manifold on my 110. The ports were restricted by buildup and was causing a lot of black smoke due to running rich as it wasn't getting enough air. I was very aware that if it got much worse, the whole manifold would need removing and on a DW10 that basically means engine out.

This is how it looked before (not my picture, but it looked almost identical in terms of buildup):



I removed as much of the buildup as I could myself with a screwdriver and patience, and then handed it over to the Terraclean chaps.

Before + After:



Drives like a new car now, much less turbo lag, almost no smoke as well as smoother running. I'd wholeheatedly recommend anyone with this issue gets this done - well worth the money.

Ben

[frog]

HI fattail95

Thanks for your clear pictures!

Did you actually remove the intake manifold from the engine block in order to clean it? Or did you leave it in place?

How did you clean it, which tools did you need? On the TerraClean web site I found these:

http://www.terraclean.net/product.php?id=56
http://terraclean.net/product.php?id=57

Is that what you used?

My DW10ATED is producing quite some smoke during accelerating. I think this might be due to clogging of the air intake. I want to clean up everything as you did, just need to know the steps involved.

I am wondering why the motor management allows for smoke. The inlet air flow is metered, and also the turbo boost pressure is measured (isn't it?). So the ECU can measure the amount of inflowing air and adjust the fuel injection quantity accordingly, in such a way that no smoke should be produced. But apparently the ECU does not do this. Or does it?

Cheers!

[fattail95]

Those are the correct tools, yes.

The intake manifold was left in-situ as it's basically an engine-out job to remove it. The elbow is simply removed (two bolts) and the cleaner is sprayed into there, mine was quite expensive to do as so much cleaning fluid was required (very heavy deposits). The chaps spent a good 3 hours solid on it, but afterwards the intake manifold was left like new! It also cleans in the cylinder head itself and around the valves which is often ignored.

The ECU does not allow for smoke, assuming the entire intake/exhaust system is sealed, which after 15 years often is not. Smoke is produced typically when there is a boost leak, this is because the ECU opens the wastegate when the turbocharger is producing the regulated pressure (2000mbar absolute), however when there is a leak the turbo will simply spool faster to produce the same boost. This means the MAF sensor will read the same value it would without a leak, but the ECU has no way of knowing there is air leaving the system so it presumes the engine is using it all and responds by adding the normal amount of fuel. This knocks the stoichiometry off and the AFR becomes rich, meaning high EGT's and black smoke. There are several common locations for boost leaks on these:

- Intercooler (look for oil deposits on the bottom)
- Plastic turbocharger outlet pipe on the back of the engine
- Loose hose clamps allowing air to pass by

Once you're sure you have a fully sealed inlet system, and still have smoke, move onto the exhaust. A leaking EGR valve (which I had) allows exhaust gas to pass into the engine bay, meaning the turbocharger does not receive the full air flow and increases spool times (smoke coming on boost) and if bad enough will prevent the engine building correct boost levels. Removing the EGR system altogether and replacing the heat exchanger with the straight through pipe (see here: viewtopic.php?f=1&t=23556) solved my smoke issue, as well as simplifying the engine bay a great deal.

Hope that helps, if you have any further questions please don't hesitate to ask.

Best Regards
Ben

[frog]

Thanks Ben, very useful information. I think my problem is the same as yours. If I press the accelerator very gently, and give it a few seconds to get used to the idea we're going to speed up, then no smoke, even if in the end the pedal is to the metal. But if I stamp on it ... big clouds of smoke .

Apart from visual check, is there any "do it yourself" way to check for leaks in the air intake system? Like putting the system under pressure, with the engine off (silent) to hear if air leaks out somewhere. Or put a smoke generator in front of the air inlet, rev up the engine, and check if the smoke comes out somewhere. Maybe ask a local junkie to roll a big joint and puff it in front of the air inlet .

I think anyway that the time is right to blank off the EGR valve, as you did. I already have a set of blanking plates. Did you have to update the ECU software for that? I think mine will need to be tweaked. I have an MPPS cable and was able to read the flash of the ECU into my laptop.

I cannot find any companies that offer TerraClean here in the Netherlands. I found a nearby company that offers cleaning with "MotorVac DieselTune"; that seems to be a close alternative. Does anyone have experience with that?

[frog]

Maybe ask a local junkie to roll a big joint and puff it in front of the air inlet .

Haha turns out that I was not the first one to think of this. Some-one created a "robot" version of a super junkie, in the form of a jar with three smoking joints in it, LOL:

https://www.youtube.com/watch?v=BITZ-MsPRzM

Another one here: https://www.youtube.com/watch?v=zMok2y05jNE

A lot cheaper than this: http://redlinedetection.com/products/hd-powersmoke

[fattail95]

Thanks Ben, very useful information. I think my problem is the same as yours. If I press the accelerator very gently, and give it a few seconds to get used to the idea we're going to speed up, then no smoke, even if in the end the pedal is to the metal. But if I stamp on it ... big clouds of smoke .

Apart from visual check, is there any "do it yourself" way to check for leaks in the air intake system? Like putting the system under pressure, with the engine off (silent) to hear if air leaks out somewhere. Or put a smoke generator in front of the air inlet, rev up the engine, and check if the smoke comes out somewhere. Maybe ask a local junkie to roll a big joint and puff it in front of the air inlet .

I think anyway that the time is right to blank off the EGR valve, as you did. I already have a set of blanking plates. Did you have to update the ECU software for that? I think mine will need to be tweaked. I have an MPPS cable and was able to read the flash of the ECU into my laptop.

I cannot find any companies that offer TerraClean here in the Netherlands. I found a nearby company that offers cleaning with "MotorVac DieselTune"; that seems to be a close alternative. Does anyone have experience with that?

I would also replace the MAF sensor on your car if you haven't already, they start to become inaccurate after a few years and give slightly off readings, not so much that you'd know there was a fault but when you install a new you'll notice the difference (Eric will attest to this). You could probably pressure test the system using the intercooler MAP sensor pipe, if you could hook up either a vacuum pump or pressurise the system you could watch the air pressure and see if it changes at all.

The EDC15C2 isn't the cleverest of ECUs, you will be able to blank the EGR and not have a MIL or anything, all that will happen is you will have a dormant code stored along the lines of "air flow higher than expected", but it will not cause any running issues/limp mode on the DW10.

[frog]

I would also replace the MAF sensor

Thanks I will do that.

Is it an idea to just disconnect the electric plug that goes into the solenoid on the bulkhead? That should keep the EGR valve closed, wouldn't it?

Not as a long-term solution, but just to see if the smoke is gone.

My 406 has an "air doser" (there are 3 solenoids on the bulkhead), I guess it would be a good idea to disconnect also the solenoid that operates the air doser?

[GingerMagic]

Hi, you need to keep the connectors plugged in to keep the ECU happy, but you can remove the rubber pipe from the solenoids ( EGR and Doser - its the pipe nearest the bulkhead... ) and blank the open pipe with a screw.

[frog]

Hi, you need to keep the connectors plugged in to keep the ECU happy, but you can remove the rubber pipe from the solenoids ( EGR and Doser - its the pipe nearest the bulkhead... ) and blank the open pipe with a screw.

Thanks!

[frog]

Hi, you need to keep the connectors plugged in to keep the ECU happy, but you can remove the rubber pipe from the solenoids ( EGR and Doser - its the pipe nearest the bulkhead... ) and blank the open pipe with a screw.

Done. See pictures:


Blocked tube to EGR value.


Blocked tube to air doser.

Result: smoke is gone!! Well, for 95%.

Immediately noticed the engine is running smoother, more quiet. Noticed directly that the idling has gone up slightly (~875 rpm), but only when coasting and engine in free running. When stopped (no longer rolling) it returns back to its normal ~825 rpm.

It is also picking up more swiftly. Makes it possible again to tailgate behind that big fat Porsche Cayenne at 160km/h at an affordable fuel consumption thanks to the slipstream .

The smoke during acceleration is gone! I only noticed a short puff when putting the accelerator all the way down for the first time after the engine had completely warmed up. Maybe some old stuff still caught up in the exhaust.

No engine malfunction lights, no message on LCD display (yet, after 200 km).

I will still check for air inlet leaks, visually, when I do my pre-MOT checkup at the local "do-it-yourself" garage. I will pay special attention to the rubber pressure pipe underneath, leading to the intercooler. And I will check and clean the MAF.

Hope this leads to easier passing MOT than last year, when I had to drive the motorway in third gear for half an hour to blow out all the soot .

[fattail95]

Good effort there! Now is the time to change that way overdue fuel filter, and you may as well do the oil and air filter while you're at it. With no EGR you'll also notice MUCH cleaner oil for far longer too, which can only be a good thing.

[frog]

Good effort there! Now is the time to change that way overdue fuel filter, and you may as well do the oil and air filter while you're at it. With no EGR you'll also notice MUCH cleaner oil for far longer too, which can only be a good thing.

Yeah, you may be right. MOT is due end december, might as well combine my pre-MOT checkup with a good cleanup/maintenance. The air filter is a K&N filter (also in for now at least 70.000 miles, plus the miles it was used in my previous 406 saloon), not sure whether to clean it or to replace it. Oil is now 21000 miles, very black (but it was already black again after the drive home from the oil change).

[frog]

The air filter is a K&N filter (also in for now at least 70.000 miles, plus the miles it was used in my previous 406 saloon), not sure whether to clean it or to replace it.

http://www.efkaimport.nl/Subpaginas/9/L ... _Olie.html says:

"Hoe vaak moet het K&N filter worden gereinigd?
[...] Het kan zijn dat een filter bij rally-cross om de 150 km schoongemaakt moet worden en bij een personenauto pas na 200.000 km. Op z’n laatst dient een K&N filter schoongemaakt te worden als er een vuillaag van 2-3 mm ontstaan is."

In English:

"How often should the K & N filter be cleaned ?
[...] It may be that in rally -cross a filter must be cleaned at 150 km [100 mi] and in a passenger car not until after 200,000 km [125.000 mi]. At the latest a K & N filter should be cleaned if there is a dirt layer of 2-3 mm."

125.000 miles... wow

[fattail95]

Good effort there! Now is the time to change that way overdue fuel filter, and you may as well do the oil and air filter while you're at it. With no EGR you'll also notice MUCH cleaner oil for far longer too, which can only be a good thing.

Yeah, you may be right. MOT is due end december, might as well combine my pre-MOT checkup with a good cleanup/maintenance. The air filter is a K&N filter (also in for now at least 70.000 miles, plus the miles it was used in my previous 406 saloon), not sure whether to clean it or to replace it. Oil is now 21000 miles, very black (but it was already black again after the drive home from the oil change).

Without trying to sound rude here, you clearly don't respect your car much if you're running the same oil after 21k - that really is appalling. Get the oil changed right now and sort out your maintenance schedule, I know these cars are hard to hurt but come on you have to make some effort...

[frog]

Without trying to sound rude here, you clearly don't respect your car much if you're running the same oil after 21k - that really is appalling. Get the oil changed right now and sort out your maintenance schedule, I know these cars are hard to hurt but come on you have to make some effort...

Haha no problem, I am caring very much about my car. I wash it very often and I'm the one in our neighborhood who is the most often vacuum cleaning the interior (very necessary with 4 kids ).

Last oil change was after 40.000 mi. It's not that I don't want to change it, it's just that I think it doesn't really matter. There was a lot of discussion a few years ago on TV here about whether or not it is necessary to change oil as often as is currently done. A consumer show interviewed a guy who hadn't changed oil for 200.000 km (125.000 mi) and was still rolling happily.

Found on http://dnr.louisiana.gov/assets/TAD/edu ... el/a/a.htm :

"Present fleet tests of 90,000 mile drain intervals have found the oil free and clean of deposits and suitable for continued use."

Would you be open to the (faint) possibility that changing oil might, just might, be possible at much longer intervals? I am, and I am willing to take the risks that might be involved.