Skip the auto shop - Our mechanics make house calls

Q: Do I really need to use high octane fuel or can I use mid grade (occasionally)?

asked by on

is it necessary to use the higher octane gas. i sometimes use mid grade and I don't hear a knock or ping. with the price of gas saving a few dollars at fill-up seems like it worth it

My car has 6600 miles.
My car has an automatic transmission.

A: If your vehicle is required to use high oct...

If your vehicle is required to use high octane fuel, then using anything else can cause damage to the pistons and valves in the engine. When you say you cannot hear any pinging when you are using mid grade fuels then you need to be sure since not all pinging can be heard by the human ear. The pinging may be happening so light that you would not be able to hear it. Any pinging is not good to the engine and can burn holes in the tops of your piston. Pinging is the fuel is igniting before the engine wants it to and ignites before the ignition sparks it. This is why it is called pre-ignition. I recommend not using any mid or low octane fuels for this vehicle.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: AFTER STARTING UP AND WARMING I DIRECTLY PUT THE GEAR ON D BUT THE CAR DOES NOT MOVE

Hi there: Sometimes this issue is caused by damaged transmission shifting linkage or an electrical sensor that helps monitor the the operation of the transmission. Without being there to complete a diagnostic scan or physical inspection; it's very hard to...

Q: My AC bearings are making noise - what does this mean?

Hi there. I am not quite clear which bearings or other components you may be hearing. The most likely noises coming from the engine compartment would be the AC compressor clutch bearing, and the compressor itself. While the clutch bearing...

Q: Cost to repair cracked transmission cover after item hit skid plate 2015 Acura MDX

Hi there - I recommend a transmission inspection ASAP to confirm and evaluate any damage from this impact. Even if not leaking now, if something is fractured or cracked, a major fluid loss and repair could lurk around the corner....

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.