Broken exhaust valve
- Thread starter Tommiee
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If you find evidence that the plug electrode failed on the old plug after a tune they should pay for all the repairs and refund you on your tune.
But I have 0 experience with tuning so don't explode on anyone with my advice haha.
Personally, I would refund everything if you were my customer and I wouldn't even argue provided a mark was made in the valve seat in the head from a metal piece.
If that mark has a squared looking shape I'd open my till and start counting out the bills into your hand.
This could really harm a tuning shop rep if this is the case. This would be IMO "Amateur Hour" level of fail on their part.
Keep us posted with what you find!!!
But I have 0 experience with tuning so don't explode on anyone with my advice haha.
Personally, I would refund everything if you were my customer and I wouldn't even argue provided a mark was made in the valve seat in the head from a metal piece.
If that mark has a squared looking shape I'd open my till and start counting out the bills into your hand.
This could really harm a tuning shop rep if this is the case. This would be IMO "Amateur Hour" level of fail on their part.
Keep us posted with what you find!!!
My gaping tool bends the electrode very close to the attachment point. This was a failure of the electrode tip, it seems to me and there is also much degradation of the center electrode.
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accelerating hard to 250 km/h, had to let go off the throttle for another car and when i went back on it, after a few seconds the power was gone and CEL starts flashing
That plug was almost with certainty not damaged from bending the ground electrode. IMO it falls into the detonation/pre-ignition category of damage, what is the heat range of these plugs and how do the others look?
This happens when the tips glow red hot, everything get hot enough to melt the piston top to some degree then the fuel explodes blowing the tip off.
The black could be carbon from the piston head. I have to question why the tuner didn't replace the plugs or at least pull them to check them and the heat range when doing the tune.
Whatever happened apparently happened almost instantly, I'm not sure about the bad plug theory. You were on it then backed off then jumped right back on it again, at that point the plug temps went way up. These DI injectors are high pressure so their position in the fuel rail is unimportant but there have been numerous reports of injector issues causing damage.
A common performance replacement is from the RS4, its a better injector all round. I have no idea really I have have the engine here and don't know how it was built or with what parts, just throwing some stuff out.
accelerating hard to 250 km/h, had to let go off the throttle for another car and when i went back on it, after a few seconds the power was gone and CEL starts flashing
That plug was almost with certainty not damaged from bending the ground electrode. IMO it falls into the detonation/pre-ignition category of damage, what is the heat range of these plugs and how do the others look?
This happens when the tips glow red hot, everything get hot enough to melt the piston top to some degree then the fuel explodes blowing the tip off.
The black could be carbon from the piston head. I have to question why the tuner didn't replace the plugs or at least pull them to check them and the heat range when doing the tune.
Whatever happened apparently happened almost instantly, I'm not sure about the bad plug theory. You were on it then backed off then jumped right back on it again, at that point the plug temps went way up. These DI injectors are high pressure so their position in the fuel rail is unimportant but there have been numerous reports of injector issues causing damage.
A common performance replacement is from the RS4, its a better injector all round. I have no idea really I have have the engine here and don't know how it was built or with what parts, just throwing some stuff out.
You were at WOT (or close to it) and throwing fuel at the valves, which helps cool them, then backed off (closed throttle) which might have created a lean condition, the exhaust valve might have got hot and brittle at that point. There is a lot of force trying to throw the valve apart at that speed, so a crack is more than enough to cause a failure.
Pure speculation; it's hard to say exactly without MUCH more knowledge of the specific motor and conditions. But something to think about.
Pure speculation; it's hard to say exactly without MUCH more knowledge of the specific motor and conditions. But something to think about.
PFR7S8EG NGK is the sparkplug. Should be correct for stock untill stage 2+, lots of guys running the same amount of power on these plugs, the other 3 looked perfect but were also a bit rusty outside. My guess is that the engine was high pressure washed before sale, thats why they were rusty probably. They were on my to do list to change with the next oil change, thought they were good to go untill next change because the engine has only done 35k miles..
The k04 injectors should be no problem as they allow sufficient fuel for 420 hp setups, i'm well below and didn't have any lean conditions before. More like a bit rich, puffing some black soot out of the back on wot, like any other tfsi.
Also the fuel was a very high quality high octane fuel ( Competition RON102 ) and it was mapped on 98/100 Ron with zero timing pull on that. Because i wanted to be able to drive on pure RON98 as 102 is difficult to get.
Also combined with the black plug only on that cil.. maybe it uses oil only on that cil and doesnt oil lowers ocane big time? Might be the cause of oil ?
The k04 injectors should be no problem as they allow sufficient fuel for 420 hp setups, i'm well below and didn't have any lean conditions before. More like a bit rich, puffing some black soot out of the back on wot, like any other tfsi.
Also the fuel was a very high quality high octane fuel ( Competition RON102 ) and it was mapped on 98/100 Ron with zero timing pull on that. Because i wanted to be able to drive on pure RON98 as 102 is difficult to get.
Also combined with the black plug only on that cil.. maybe it uses oil only on that cil and doesnt oil lowers ocane big time? Might be the cause of oil ?
Let us know what you find out.
I remember reading that many Subaru Forester XTs and WRXs were found to have damaged plugs during the LSPI recall, and I remember seeing at least one picture that looked much like the one you posted. The fact that you experienced damage when you dialed back on the throttle is also consistent with LSPI.
I am assuming that this is a DI turbo? There was a huge thread on a Veloster Turbo site with dozens of stories about DIT engines being blown at low RPMs.
I am assuming that this is a DI turbo? There was a huge thread on a Veloster Turbo site with dozens of stories about DIT engines being blown at low RPMs.
Yes it is DI Turbo. It's the 2.0t fsi engine.
Herrstig, Trav, and Johnny are making a lot of sense in what they are writing.
I would still refund you on the Tune at least if my employees never even pulled the plugs to check the gap and read them for engine condition before starting. This is 101 level stuff here really.
A good Mechanic would have thrown one in a ziploc and given it to the S.A. to advise you that you need (ABSOLUTELY) new plugs before the Tune or I wouldn't even proceed until you supply new ones or sign off to buy the plugs to be added to the bill.
Just on the CHANCE the old plug did your valve in, in good faith I'd give you the benefit of the doubt and refund your money.
If it was a detonation, there is no denying a new plug MAY have held together (but maybe not) but that is were a good shop will side with you, and a bad shop would destroy their name over a few bucks (even worse than "ruining" your engine IMO).
Heck, on second though, based on the plug [censored] I'd fix your ride and re-tune it for free. It is just that bad to me I guess, and on principle that is how I'd deal with it I guess.
These, to me, are the "Protections" dealing with pros and paying the bucks implies.
Again, maybe Pros don't pull plugs before a tune. I never dealt with a tuner shop. Tuning is an expensive hobby if they risk your kit without any basic sense applied before they Tune. Like tuning a broken guitar or one with rusty strings that are 10 years old.
Put on new strings then tune the guitar, not the other way around.
Keep us posted.
I would still refund you on the Tune at least if my employees never even pulled the plugs to check the gap and read them for engine condition before starting. This is 101 level stuff here really.
A good Mechanic would have thrown one in a ziploc and given it to the S.A. to advise you that you need (ABSOLUTELY) new plugs before the Tune or I wouldn't even proceed until you supply new ones or sign off to buy the plugs to be added to the bill.
Just on the CHANCE the old plug did your valve in, in good faith I'd give you the benefit of the doubt and refund your money.
If it was a detonation, there is no denying a new plug MAY have held together (but maybe not) but that is were a good shop will side with you, and a bad shop would destroy their name over a few bucks (even worse than "ruining" your engine IMO).
Heck, on second though, based on the plug [censored] I'd fix your ride and re-tune it for free. It is just that bad to me I guess, and on principle that is how I'd deal with it I guess.
These, to me, are the "Protections" dealing with pros and paying the bucks implies.
Again, maybe Pros don't pull plugs before a tune. I never dealt with a tuner shop. Tuning is an expensive hobby if they risk your kit without any basic sense applied before they Tune. Like tuning a broken guitar or one with rusty strings that are 10 years old.
Put on new strings then tune the guitar, not the other way around.
Keep us posted.
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Agree with you all. Have to be sure that the spark plug has caused this before i can get to any action about money refunding. will be doing it with a mechanic friend so the bill will be kept a bit lower hopefully than when done by a shop.
As said before the tuning shop wants my car back on the dyno when it's fixed to check. I trust the company, they did 100 miles and wrote 16 tuning files before they were satisfied and took their time. They advised me to do BG Intake clean because they could see on the dyno that it had carbon deposits ( they log engine data during dyno'ing so they can see that back in the performance curve ). i did let them to it.
For any interested people, here is the dyno sheet.
As said before the tuning shop wants my car back on the dyno when it's fixed to check. I trust the company, they did 100 miles and wrote 16 tuning files before they were satisfied and took their time. They advised me to do BG Intake clean because they could see on the dyno that it had carbon deposits ( they log engine data during dyno'ing so they can see that back in the performance curve ). i did let them to it.
For any interested people, here is the dyno sheet.
Anyone know about 5252rpm and what that graph above is missing?
Originally Posted By: Planb
Anyone know about 5252rpm and what that graph above is missing?
Yes, The Torque & Horsepower curves ALWAYS cross at 5,252rpm on every dyno printout I've ever seen,
Anyone know about 5252rpm and what that graph above is missing?
Yes, The Torque & Horsepower curves ALWAYS cross at 5,252rpm on every dyno printout I've ever seen,
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Mathematically Horsepower = Torque at 5,252 no matter what. (If torque measured in Ft/lbs)
Not sure what the dyno operator has done with the scaling but if the horsepower is the correct # and you make 366hp at 6500 RPM, then you are making 296 Ft/lbs at 6500, but the graph shows roughly 400, not mathematically possible.
At 4500 (peak torque) it shows you are making about 300 HP, if the horsepower and RPM are correct, your actual torque at 4500 RPM equals 350 Ft/lbs. 470 FT/lbs at 4500 with 300 HP is not mathematically possible.
EDIT::
The torque figure in that graph is in Newton-meters. The numbers are correct, us yanks just aren't used to seeing dynos in Newton meters. We like Ft/lbs
Not sure what the dyno operator has done with the scaling but if the horsepower is the correct # and you make 366hp at 6500 RPM, then you are making 296 Ft/lbs at 6500, but the graph shows roughly 400, not mathematically possible.
At 4500 (peak torque) it shows you are making about 300 HP, if the horsepower and RPM are correct, your actual torque at 4500 RPM equals 350 Ft/lbs. 470 FT/lbs at 4500 with 300 HP is not mathematically possible.
EDIT::
The torque figure in that graph is in Newton-meters. The numbers are correct, us yanks just aren't used to seeing dynos in Newton meters. We like Ft/lbs
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Sorry Tman220, that you like ft/lbs.. we count in Nm's only so don't have a ft/lbs graph. I can imagine that it looks strange to you guys then
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Any update on the post mortem analysis?
Not yet, my mech friend just came back from vacation and we'll be doing it in the evenings so i hope we can get started in the next few days
As promised, i will share some pics with u guys. Piston is shot, exhaust valve is broken. Also notice the big amount of oil on the cilinder head @ cilinder 4. the exhaust valves and manifold from cil 4 are full of oil too.
Probably started detonating badly because of the oil in the cilinder. others look perfect. My tuner is gonna help me out on this, paying for parts as goodwill ( they are still sure their software isn't the problem but they wanna take away my worries as they like me as their customer, their words )
will take some time to fix as we have to do it on our free days, i'm lucky to say that the cilinder bore is magically unscuffed..
Probably started detonating badly because of the oil in the cilinder. others look perfect. My tuner is gonna help me out on this, paying for parts as goodwill ( they are still sure their software isn't the problem but they wanna take away my worries as they like me as their customer, their words )
will take some time to fix as we have to do it on our free days, i'm lucky to say that the cilinder bore is magically unscuffed..
Not as bad as I expected but I would check that rod carefully also.
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