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3.3TT How Do These Pistons Look?

Metalmania82

Stinger Enthusiast
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Reading, PA
Got new Denso plugs in over the weekend, gapped to 22, same issue this morning driving to work. Back to square one!
 

cncBilly

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Metalmania82

Stinger Enthusiast
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Reading, PA
Of course
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springspeed

Newish Member
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On picture number 2 the edge of the piston doesn't look good. Excessive heat. The pistons are really clean, that's not really good. With your tuner can you add fuel? A lean condition creates lots of heat on the pistons. I hate to say this but I have seen pistons that look like that and the ring lands are usually cracked. What's oil consumption like?
 

Spaceme17

Active Member
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Pistons look fine.

Everyone "seeing" things on the pistons, the pictures are too grainy to see any fine detail. And if you are seeing anything, it is most likely some carbon deposits. Only way to really inspect the pistons would be the pull the heads.

Most likely if there is a hiccup at cold start, the likely cause is build up on intake valves.

I would take the time to pull the intake manifold and check out the valve build up and do some cleaning if there is any deposits.
 

Metalmania82

Stinger Enthusiast
514
116
43
Reading, PA
On picture number 2 the edge of the piston doesn't look good. Excessive heat. The pistons are really clean, that's not really good. With your tuner can you add fuel? A lean condition creates lots of heat on the pistons. I hate to say this but I have seen pistons that look like that and the ring lands are usually cracked. What's oil consumption like?
No consumption at all. As far as adding fuel, not sure if the JB4 can do that but I'll look into it, thanks.
 

Metalmania82

Stinger Enthusiast
514
116
43
Reading, PA
Pistons look fine.

Everyone "seeing" things on the pistons, the pictures are too grainy to see any fine detail. And if you are seeing anything, it is most likely some carbon deposits. Only way to really inspect the pistons would be the pull the heads.

Most likely if there is a hiccup at cold start, the likely cause is build up on intake valves.

I would take the time to pull the intake manifold and check out the valve build up and do some cleaning if there is any deposits.
Any point, in your opinion, to run a GDI specific cleaner through the intake, like the kit that CRC sells?
 

Vermillion

Member
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Yeah, new sparkies were never going to fix it.. I took the manifold off and cleaned it with some Wynns, different car like (Alfa 159 2.4 diesel) but the basic premise is the same. I'd also seriously recommend at some point getting it on a diagnostics machine to see if its sucked deposits into the fuel system, my Piezo's had suffered to due to the fact. It's easy to read, your injector spray correlation values will be within a 0+ / - value, if any of them look off (like unusually high or low you have injector issues).

It's one of the other major causes of poor idles, starting issues, fuel economy problems and weird power problems. Also I don't know about US spec cars but over here we require PPF's (petrol particulate filters) or DPF's (diesel) and EGR's, when an EGR gets clogged guess what happens? Poor idles etc. etc. I've cleaned that out on several cars including petrols.

Finally it could be a sensor issue but if you find any clogging (buildup) then you know it isn't a sensor. It's a right job when I did it, had to drop the subframe just to get to it.. If you're not thoroughly confident with engines I'd probably leave it to someone else, also any information stated here is discussion only. Essentially if you mess something up it's on you :).!
 

Metalmania82

Stinger Enthusiast
514
116
43
Reading, PA
Yeah, new sparkies were never going to fix it.. I took the manifold off and cleaned it with some Wynns, different car like (Alfa 159 2.4 diesel) but the basic premise is the same. I'd also seriously recommend at some point getting it on a diagnostics machine to see if its sucked deposits into the fuel system, my Piezo's had suffered to due to the fact. It's easy to read, your injector spray correlation values will be within a 0+ / - value, if any of them look off (like unusually high or low you have injector issues).

It's one of the other major causes of poor idles, starting issues, fuel economy problems and weird power problems. Also I don't know about US spec cars but over here we require PPF's (petrol particulate filters) or DPF's (diesel) and EGR's, when an EGR gets clogged guess what happens? Poor idles etc. etc. I've cleaned that out on several cars including petrols.

Finally it could be a sensor issue but if you find any clogging (buildup) then you know it isn't a sensor. It's a right job when I did it, had to drop the subframe just to get to it.. If you're not thoroughly confident with engines I'd probably leave it to someone else, also any information stated here is discussion only. Essentially if you mess something up it's on you :).!
Thank you for that insight and information. I'll add this to the list of possibilities and things to look into.
 

Spaceme17

Active Member
129
77
28
Any point, in your opinion, to run a GDI specific cleaner through the intake, like the kit that CRC sells?
I haven't tried the GDI cleaner that CRC sells but I am sure that it will help.

The other option is to manually clean the valves.

I haven't done it on my stinger but I have done it on an Audi with DI. The basic process was to remove the intake manifold, pour some carbon cleaning solvent into the intake track of the valves that are closed, then use wire brushes and plastic picks to physically disslodge the deposits. Then vacuum out the liquid and debri. Repeat until clean. Rotate the engine until the remaining valves are closed and clean them.

Some people have also used crushed walnut shells and a vaccum cleaner adapter to capture the walnut shells.
 

springspeed

Newish Member
7
6
3
Pistons look fine.

Everyone "seeing" things on the pistons, the pictures are too grainy to see any fine detail. And if you are seeing anything, it is most likely some carbon deposits. Only way to really inspect the pistons would be the pull the heads.

Most likely if there is a hiccup at cold start, the likely cause is build up on intake valves.

I would take the time to pull the intake manifold and check out the valve build up and do some cleaning if there is any deposits.
A compression check is what is needed. As for the edge of the piston, its not too grainy to see whats up.
 

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