Spark Plugs?

[RandomX]

Hi All,

First time i've changed my own spark plugs... Pretty easy apart from removing the coil packs :/

Anyway here is a picture of one i removed... Does it look normal for a 20000k old spark plug?

Cheers,

Josh : )

[brad]

More or less. Possibly a bit hot?

It's a platinum or iridium so it only needs changing every 60,000-90,000 (depends on the plug)

[Lucas_R]

Looks like it's been running a bit hot to me. See chart attached. Caused by lean fuel mixture (which leads to hotter temperatures in the combustion chambers. Petrol has a cooling effect, so a engine that runs richer will run cooler).

You might want to try a cooler spark plug.

[nomadx38]

What brand of plugs are they if you don't mind me asking? NGK / Champion / Bosch?

They don't look very heathy but I would have thought with the tune it would be running more rich. Could also be oil fowling considering the amount of oil these engines drink

[RandomX]

They're NGK Iridium IX... I decided to change them as the engine was idling rough and occasionally misfiring when cold... Also very wet soot at the exhaust... Should the plug have oil all over it?

The plugs were gapped to 0.8mm... (apparently)

Josh

[nomadx38]

Ahh ok yeah the NGK iridium IX are awesome spark plugs, really good performance. I wanted to get some for my 1.2tsi but they don't make them for it so I had to get the OEM laser iridium.

And it's allways an idea to check the gap size becuase sometimes they can get squashed in transport.

[gavs]

Lean fuel delivery. Common trait with the factory engine mapping but I know yours is running the apr tune so maybe speak with the guys at apr and shoot them the pics.

[LunchboxVRS]

Not saying this pertains to the polo but Some engines don't like iridium's. Iv had a thew bikes/cars that would not work no matter what the gap/heat range of the iridium plugs are. My aprilia would only run properly on stock plugs before and after it was rebuilt for racing and tuned.
I would put some clean stock ones back in for a bit and see if you get the same result.

[nomadx38]

Not saying this pertains to the polo but Some engines don't like iridium's. Iv had a thew bikes/cars that would not work no matter what the gap/heat range of the iridium plugs are. My aprilia would only run properly on stock plugs before and after it was rebuilt for racing and tuned.
I would put some clean stock ones back in for a bit and see if you get the same result.

The OEM plugs for all VW's are all NGK Laser Iridium. These are spark plugs with a iridium tip which is lasered onto the base and a platinum plate welded onto the arm. They are made this way to give about 60-90k km out of the plugs.

In comparison the iridium IX are offered as a high performance alternative becuase they create a more powerful, hotter spark. They do this by reducing the quenching effect which is where the spark length varies which means to could misfire or start the flame front late.

The IX plugs do this by having a longer and much thiner piece of iridium on the base (OEM is .9mm and the IX is .5mm ~) and having a triangle pointed arm with a platinum plate so that the spark is allways directed towards the centre of the arm, not the sides.

Technically speaking there is no reason why it shouldn't work...

[The_Punisher]

Anyone with a DP tried gapping the spark plugs less than 0,8mm?. I'm waiting for the coiler puller set I ordered to arrive, I'm going to set my Polo's spark plugs to 0,6mm as required for the PnP ChipBox. I have the stock DP and a straight pipe exhaust.

Between 4000rpm and 5000rpm there is a dip on the dyno graph due to possible spark blowout. Regapping the spark plugs will hopefully fix this. Maximum power will also then hopefully peak over 6000rpm. Stock power 131wkw is at 6200rpm.