White Sparkplugs

[joenorr]

The sparkplugs on our 1992 Geo Metro seem to be burning sort of white. Is this pretty much what they all are?

[ydeardorff]

That sounds like its running lean, or theirs impurities in the gas.

They should be a nice golden brown color, almost a tan. If they are black your running rich. And if they are wet, or oily, you have problems!

heres a quote from another website: http://www.classictruckshop.com/club...park/plugs.htm

Incorrect Heat Range APPEARANCE: The effects of high temperature on a spark plug are indicated by clean white, often blistered insulator. This can also be accompanied by excessive wear of the electrode, and the absence of deposits.
CAUSE: Check for the correct spark plug heat range. A plug which is too hot for the engine can result in overheating. A car operated mostly at high speeds can require a colder plug. Also check ignition timing, cooling system level, fuel mixture and leaking intake manifold.
RECOMMENDATION: If all ignition and engine adjustments are known to be correct, and no other malfunction exists, install spark plugs one heat range colder.




Ash (Lead) Deposits APPEARANCE: Ash deposits are characterized by light brown or white colored deposits crusted on the side or center electrodes. In some cases it may give the plug a rusty appearance.
CAUSE: Ash deposits are normally derived from oil or fuel additives burned during normal combustion. Normally they are harmless, though excessive amounts can cause misfiring. If deposits are excessive in short mileage, the valve guides may be worn.
RECOMMENDATION: Ash-fouled plugs can be cleaned, gapped and reinstalled.

[joenorr]

So if the sparkplugs are like new white and engine is running lean, what's the cure? Car runs ok..........

[Johnny Mullet]

Does it loose any coolant?

[joenorr]

Car runs great , just have hotter burning plugs

[redpepe]

hi joe and all,

i'm having similar symptoms. i just rebuilt the engine ['91,1.0 manual with 326k] and it's finally broken in i think ... after 600 miles. the mileage went from 48.4 on the first fill up to 68.5 on the third. the spark plugs went from tan to white and now i'm concerned by the lean mix. i've experienced this before with rebuilt engines .... break in then very high mileage for a while, light gray exhaust pipe, etc. and then it drops back to expected figures. very pleased but i don't want to do any damage. i've started pushing the break in harder to run excess fuel through the engine but so far the plugs are still white. i checked for vacuum leaks and other problems but couldn't find any.

btw ..... i was getting 'oil pharts' from blowby until the parts seated properly .... at least that's the current speculation. everything else seems to be going well.

yesterday we did compression and leakdown ...... about 175psi compression and 2-3psi leakdown differential for all cylinders.

[ydeardorff]

bumped for update