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Defender Mike
5th April 2015, 11:28 AM
My EGR blank off has arrived & I will be fitting as soon as i can get hold of a gasket that didnt come with the kit. I googled Utube to find a video of how to do it yes there is one. While searching Utube i came across the something i hadnt heard about previously. Direct injection engines have carbon build up issues around the valves & manilfold. This is because no fuel mist is cleaning the back of valves or manifold. Some BMW petrol engines suffer so badly they actualy blast the carbon off using walnut shell as a blast medium. They do this with the engine still assembeld. I also read the egr is supposed to help clean the manifold & valves as the recirulated exhaust gas contains moisture that steam cleans the manifold . May be a good theory but i dont think it works in practice. Has anyone had carbon build up problems with a TD6 or had a good look at the valves with the manifold off .
Mike:)

rar110
5th April 2015, 07:47 PM
I read a while back the early NT 2007 Pajeros had carbon build up. The solution was manifold off for a clean.

Our Peugeot was suspected of having carbon build up as the cause of engine surging. I was charged for some chemical treatment that was suppose to clean the manifold. An EGR blanking plate ended the problem.

donrover0
6th April 2015, 06:54 AM
Sounds like someone on Utube making a good story re "direct injection engines-- not cleaning back of valves etc". All diesels have the diesel injected into the chamber after the valves, whether indirect (chamber) or direct injection.
EGR blanking-- there shouldn't now be any carbon in the inlet manifold or back of inlet valves!

33chinacars
6th April 2015, 02:57 PM
You will find a hell of a lot of gunk in the manifold that will need cleaning out. Thick black sticky **** . Comes through from the ERG valve.

Defender Mike
7th April 2015, 04:04 PM
You will find a hell of a lot of gunk in the manifold that will need cleaning out. Thick black sticky **** . Comes through from the ERG valve.
Just got rid of the ERG valve . Used a blank of ebay. I could not believe the amount of sticky black carcenagenic looking crud in there. I will be pulling the manifold off at next service & giving it a good clean. Only driven 10 ks so far down to Avalon & back but it seems quiter & idling smoother already. Now for a remap & cat back exhaust system.:)

33chinacars
7th April 2015, 04:39 PM
I'm sure you will be happy & so will your motor :D

harlie
12th April 2015, 08:42 PM
this is an issue that has come up with the new DI petrol engines. Diesels have had DI for decades (300tdi) and I've not come across problems on a DI diesel.

VW have added a 2nd set of injectors on the mk7 GTI and R. the primary injectors in the cylinder and the 2nd set adding fuel into the manifold to prevent this issue.

Homestar
16th April 2015, 07:22 PM
I've had the head off mine, and the carbon build up was mild, but there. Nothing to get in a twist about and it had 230,000KM on it. EGR blanking was fitted a couple of years ago. Bigger problem as mentioned is the thick black sludge that will be in your inlet manifold from the EGR. It's bloody hard to shift too. I had my manifolds in my mates spin wash for 8 hours solid to loosen it all up, but the were sparkling clean when I reinstalled them. :)

I took the opportunity to pop all the valves out anyway and clean them up, as well as the inlet tracks on the head. Engine runs very smooth now, but no idea if that's anything to do with what I've done, but it sure didn't hurt. :)

Homestar
16th April 2015, 07:26 PM
Just got rid of the ERG valve . Used a blank of ebay. I could not believe the amount of sticky black carcenagenic looking crud in there. I will be pulling the manifold off at next service & giving it a good clean. Only driven 10 ks so far down to Avalon & back but it seems quiter & idling smoother already. Now for a remap & cat back exhaust system.:)

Then a transmission rebuild...

Defender Mike
17th April 2015, 05:56 PM
Then a transmission rebuild...

its going so well with the egr off i dont think i need it.

Homestar
17th April 2015, 09:35 PM
its going so well with the egr off i dont think i need it.

Good news. Yes I'm a glass half empty guy when it comes to these transmissions unfortunately.

Defender Mike
18th April 2015, 06:29 PM
Dont be so hard on yourself Babs . I was reading some reports on FullFat today about remaps . They reckon the smoothness is the big difference less gear changes to. Im thinking if i dont go drag racing it should hold out till Rhys does the big rebuild with all the new parts that are now available like billlet torque converter. Hardended valve body,carbon clutches etc . Theres even a stronger toilet roll shaft thingy . The 5l40-e is evolving Darwin would be proud.:)