Quote:
Originally Posted by 2003-4x4runner
You're right, coils USUALLY work or dont work. But overtime they loose their efficiency. Coils produce thousands of volts and a lot of heat. With 250k miles on the original coils and the heat from engine will degrade the coils. Ive owned my 4Runner almost 16 year's now and I change my plugs every 30k miles, so it wasn't the plugs. With new plugs and original coils I was getting 16 mpg. With new coils and plugs, I'm getting 18 mpg, both driving at 65 mph. The numbers don't lie.
|
that's great that was the case for your vehicle. are you suggesting thats the case for every vehicle out there? there are basic tests to check a coils voltage, 2mpg is a huge increase for just changing coils, maybe yours were actually bad.
the vast majority of vehicles out there will not see anywhere near that much of an MPG increase if any at all from a coil change, if that was the case it would be the #1 maint issue of all vehicles on the road! was just commenting about coils in general, most do not go bad at a unofficial mileage.