which destroyed my engine ?

[mk216v]

What destroyed my engine

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Vems engine controls, all parameters AFR, konck sensor, and ignition were set to secure a supply. An engine tuned for 95 octane fuel and then flooded with 98 octane. EGT about 820 * measured immediately after the turbocharger.
Siemens 630 injectors, Walbro 255 fuel pump.
The day before I saw the destruction of candles (Bosch) and all were slightly blackened.
That looks like the piston 3

http://w847.wrzuta.pl/sr/f/9rbhPSVfNEh/zdjecie-0405

1,2,4,5 look like this:

http://w54.wrzuta.pl/sr/d/5XuUGCBonup/zdjecie-0399

and here is the candle:

http://w501.wrzuta.pl/sr/f/7T40igIXp96/zdjecie-0391

[rs200]

the problem is in injector no.3 , they didn't work good and pot lots more fuel in cilinder than other 4...

if there are some other problem, there will be problem on all 5 pistons...

did you messured and check all 5 injector before install on engine..?

do you drive on 3B or ABY ECU?

[mk216v]

injectors were tested for performance and was ok. The engine is 3B, 7A exhaust shaft, coils with 2.0 TFSI
I had two instances of the engine is started immediately after he worked on four cylinders when turned off, and re-worked on five cylinders.

engine :

http://w235.wrzuta.pl/sr/f/3gLjfVZFlS6/zdjecie-0389

Running an engine after an acute:

http://w447.wrzuta.pl/sr/f/7wRDdmqAHwM/zdjecie-0377

[rs200]

hm...

are you 100% shure that injectors are fine...?

check it now, maybe something happend .

check intake and exhaust valves , maybe there is some leak.. something mehanical is problem, not electrical.. but I still beleve that injector is problem.

you sad that other 4 pistons are 100% , than something is not ok on that 3. cilinder.

we all know that 3. cilinder have problem with overheating , because they are in middle . maybe cooling is problem..

or the piston was bad allredy in factory, get to you, and you have problem.

[mcandmar]

Looks to me like severe detonation, what does the combustion chamber of that cylinder look like?

[fish]

"candles" are called sparkplugs.

[JP]

Something caused detonation. Now normally one would say running too lean or too advanced on the timing but then you'd expect to see the problem across the board.

From what I can make out of the spark plug it wasn't running lean otherwise it would either be melted away or white.

So the next thing I would look at is how much boost was being run and what exhaust manifold was being used. Cylinder number 3 on a stock manifold tends to run the hottest as all the gases from all cylinders accumulate at the collector there causing flow issues on the exhaust side of cyl three. So as you turn the boost up this becomes a major issue. 820 celsius after the turbo I would guestimate to be around 925-950 at the port depending again what manifold and turbo combo.

Also if you got a problem with piston rings on that cylinder then the extra oil being drawn up would potentially deteriorate the fuel enough in that cyl to cause the detonation. Likewise if the guides are worn and the valves are not seating properly you may find (especially on the exh valve) that you may have a burned seat which means you cannot make proper compression on the cylinder in question.

Anyway from what I can make out of the pics verything points to a mechanical issue that you are going to have to systematically find by pulling it apart.

[A80Avant]

820 to 945 is acceptable temps according to most tuners.

[mk216v]

MTM exhaust manifold is , head was renovated .all parts new , pistons wossner .

http://www30.patrz.pl/u/f/76/83/10/768310.jpg

[blackS2]

Are all five tubes of the manifold ok? Full free diameter in all 5 Tubes? Because I had a original mtm exhaust manifold in my hands with a casting defect - one tube was nearly sealed...

[repo]

Is the oil nozzle under the piston 3 ok?

Are You sure You had enough water in the engine?

Detonation all over the piston might rather be overheating than lean or ignition related. Latter ones usually chew the squishband, but leave the other areas intact.