Reading spark plugs?

[Jim Bowen 1]

i changed the plugs, leads and coilpack on my VR yesterday and noticed all the plugs seemed quite white, with quite lumpy/salty looking deposits. And on one of the plugs a chunk of the porcelin was actually missing :gag:

 

from looking around online i get the feeling it means its running lean? Could that be caused by the recent BMC cda i put on?

[dr_mat 0]

More likely because you have an air leak post-MAF and pre-cylinders. This may well have occured at the same time, but won't be directly related..

[Batty 0]

the white bit around the top?? or on the thread lower down?

if the latter i'd do an oil change sharpish :)

[mattkh 0]

....and noticed all the plugs seemed quite white,

Hi

What brand were the old plugs ?

What is a BMC cda ?

[Jim Bowen 1]

the old plugs were NGK's with the twin pointy bits (electrodes)

 

and the white bit around the top, i.e: the bit that sits in cylinder. Not sure how long ago this has happened, i usually take car to be serviced and let them decide what needs doing. (i don't think they have ever changed the leads) and the spark plugs must be 30,000 miles old i reckon.

 

am doing it all myself from now on

[Kevin Bacon 5]

Most healthy VR plugs I see usually resemble pics 18 to 24 on this page - http://www.dansmc.com/spark_plugs/spark ... talog.html

 

Shagged VRs look like pic 1 - :lol:

[Jim Bowen 1]

mine looked like a mix of 22 & 27, deffo looked white with a grainy powder coating them

[coullstar 0]

Heres what they should look like and what you dont want them to look like.

 

Does sound like your running lean but I doubt the BMC would do that.

[Jim Bowen 1]

none were oily like that, i still have them i should just take a pic