I had my VRS in for a misfire issue, and the dealers reported back that they'd found a bent spark plug. They had only been changed by them, around 6k miles ago at the 30k service. They couldn't give an answer as to why this may have happened and if there was any cause for further concern. They've apparently done new plugs, and ECU update and the oil breather pipe mod under warranty, due to some oil consumption (although well under the ludicrous VAG "tolerances").

 

My question is what can cause just one plug to bend, and should I be concerned!?

I assume they are talking about the tip/electrode and not the actual body of the plug?

 

It's likely it's the tip they are referring to and the most common way to bend (and therefore change the electrode gap) is to drop the plug on a hard surface

 

I would assume that if the above happened then the misfire would have been apparent right away.

 

The plug is screwed into the head and its tip sits at the top of the cylinder bore so these are some other possibilities

 

 

Foreign matter/item inside the cylinder

Missing washer from plug (they don't usually come off)

Incorrect plug type ie too long

Overly advanced timing and therefore extreme pressure in the cylinder (where the spark plug ignites the fuel/air mix and causes an explosion)

Connecting rod play in shell bearings allowing excessive movement of con rods and piston (very unlikely indeed and there will be many other symptoms)

Excessive carbon build up on piston crown 

 

Can't think of anything else

I assume they are talking about the tip/electrode and not the actual body of the plug?

 

It's likely it's the tip they are referring to and the most common way to bend (and therefore change the electrode gap) is to drop the plug on a hard surface

 

I would assume that if the above happened then the misfire would have been apparent right away.

 

The plug is screwed into the head and its tip sits at the top of the cylinder bore so these are some other possibilities

 

 

Foreign matter/item inside the cylinder

Missing washer from plug (they don't usually come off)

Incorrect plug type ie too long

Overly advanced timing and therefore extreme pressure in the cylinder (where the spark plug ignites the fuel/air mix and causes an explosion)

Remap issues with timing

Connecting rod play in shell bearings allowing excessive movement of con rods and piston (very unlikely indeed and there will be many other symptoms)

Excessive carbon build up on piston crown 

 

Can't think of anything else

in all fairness to the garage that did the work these OEM plugs in the skoda vrs tfsi range are very poorly made and really quite P**s poor could be manufactured wrong 

If it's bent it's been dropped

I think they meant the electrode tip?