[NSW] spark plug diagnosis

[tommygun]

Anyone know what causes this?

 

[pricey3682]

the plug is begginning to "foul up", often caused my a mixture that is too rich

 

[tommygun]

See the crack down the side of the porcelain near the electrode though?

 

[tommygun]

See the crack in the porcelain near the electrode though?

 

[pricey3682]

how old are the plugs?

 

[VR38]

Hard to tell from the photo but the electrode looks pitted from pinging.

 

[Brett_jjj]

Yeah, pinging/pre detonation can cause plugs to crack like that. Try using a higher octane fuel, especially if you like to give it a bootfull now and then.

 

[tommygun]

Plugs about 4000, I do like to give it a boot full. I use 98 ultimate al the time, what would cause detonation or pinging?

 

[tommygun]

Wouldn't I notice it pinging or predetonation?

 

[VR38]

Alot of carbon build up or if the heads have been done and too much taken off the heads to service them will raise the compression ratio too far.

What heat range are the plugs?

If there too hot that can cause it too.