Fuel

[Mike Smock]

Can a engine get to the point of being old enough that you should switch from a reg unleaded fuel to a midgrade fuel?

Topic

[college man]

If the vehicle calls for reg unleaded it should not change with age.

[James P Grosso]

If the engine has started pinging on regular then mid-grade (higher octane) may help.
Although the engine can see some carbon build up that may slightly increase compression, usually the pinging in high mileage comes from burning oil.
If the engine is not pinging, then you should not need a higher octane fuel, but you may want to add a can of fuel system cleaner.
Some gas stations advertise that their higher octane fuels have more fuel system cleaning additives that their regular fuel, but I have not seen an independent verification of this?

[Ryan Schweter]

[quote=”451Mopar” post=182865]If the engine has started pinging on regular then mid-grade (higher octane) may help.
Although the engine can see some carbon build up that may slightly increase compression, usually the pinging in high mileage comes from burning oil.
If the engine is not pinging, then you should not need a higher octane fuel, but you may want to add a can of fuel system cleaner.
Some gas stations advertise that their higher octane fuels have more fuel system cleaning additives that their regular fuel, but I have not seen an independent verification of this?[/quote]
If you have a lot of carbon buildup, that can cause pinging to, but not from compression raising. It usually causes hot spots that pre-ignite the mixture. It’d be a good idea in my mind, if you have pinging, to increase the octane of your fuel as well as decarburizing the engine, since the pinging can wreak havoc if not fixed.

[Author]

Replies