What has happened to my spark plugs?

Question

My car's spark plugs' electrode have all turned reddish in colour. My engine shows sign of "jerk" in low RPM, or while idling. What exactly has happened to my spark plugs? What are the possible causes of this?

No. The electrodes are not worn. It turned reddish, but overall the plugs are quite clean.

And yes, all the four spark plugs show the same sign.

My car is Toyota Camry automatic transmission. Quite old.

No smell of gasoline.

Answer 1

could be normal especilly if you only do short trips swap them out put on new wires ans drive it

Answer 2

The reddish color doesn't always indicate an engine problem. Sometimes spark plugs will turn reddish due to additives in low quality unleaded gas.

"Normal, but with red coating: The red coating is a result of the additives in lower-quality unleaded fuel and will be visible on the plug's ceramic insulation. The red coating is not an indication of any engine problems. "

I've also heard of Octane boosters turning spark plugs red.

Answer 3

were the electrodes worn?

what type of car? and how many miles?

was it on all the spark plugs?

usually the reddish color is present on the side of the body of the plug when its electrode is building up resistance to spark causing more heat.

Answer 4

You stated the car is quite old. It's possible the fuel tank may be rusted on the inside and it is contaminating the fuel. Have a mechanic drain some gas into a clear jar or if you have a clear fuel filter it would show up there as well.

Answer 5

And they smell of gasoline too, don't they? Running way too rich. If this is a computer-controlled, fuel-injected car (and they pretty much all are for the last five years or so) then your smog controls need attention (most likely the O2 sensor); the computer is getting bad information and increasing the fuel flow.

Answer 6

Could be lead glazing, check your timing and leads.