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Spark Plug Issue on a 100

tontonene

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I recently pulled my plugs on my 100 and noticed the two outside (1 and 4) looked normal and the two inside (2 and 3) looked like the cylinders were running rich. Anybody know what is happening? Looks like a fuel mixture issue.
 
Not likely a carb related problem. Cylinders 1&2 are supplied by the front carb, and cylinders 3&4 are supplied by the rear carb.

Maybe no problem at all. The center cylinders can run at slightly different temps than the outer ones. If the heater control valve is open, some coolant bypasses it's normal flow path & flows from between the center cylinders back to the water pump.
D
 
Thanks, Dave. I am not too worried since the car is performing properly. Just thought it odd that the plugs were not all the same.
 
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