The Wrong Fuel Can Make A Real Difference

January 7th, 2017

There are several different choices when it comes to fuel…using the wrong one may have little effect, or it can be a real problem. Here’s the breakdown.  

First off…using the wrong octane grade.

Octane grades were developed back in the days of leaded fuel and high-compression engines, to reduce “ping” or “spark knock” which could be very harmful to an engine. Modern cars, however, have knock sensors that can adjust fuel metering and timing to compensate for problems like that. Unless you’re driving a high-performance Porsche, chances are you won’t see much difference by putting a lower octane grade into your vehicle, unless maybe it’s a slight dropoff in performance or fuel economy.

Now, as for ethanol fuels…

Many newer vehicles are designed to use ethanol blend gasoline. If you run one tank of ethanol blend in a vehicle that isn’t designed for it, you probably won’t notice much difference. In the long run, however, ethanol is pretty hard on rubberized parts like gaskets, seals, and fuel lines. It’s also not as efficient as gasoline, so you may Ethanol in Marietta GA notice a dropoff in power and fuel economy as the engine computer delivers more fuel to try and compensate for the difference.

Diesel into a gasoline engine, or vice versa? Bad news.

Putting diesel into your gas-engine car isn’t likely, or at least you’d have to try pretty hard to make it happen…since the fuel nozzle of a gas-engine car is smaller than the pump nozzle for diesel. If it were to happen, you’d notice the car running poorly and smoking like crazy until the diesel had run through the system. You’d also probably notice the distinct smell of diesel as you fueled up!

It’s a lot easier to put gasoline into a diesel engine, though; the smaller pump spout fits easily into the nozzle of a diesel tank. Diesel fuel doesn’t ignite easily, and diesel engines rely on extremely high compression to ignite the fuel and run. That’s why they can easily run on cooking oil or other diesel substitutes. Introducing very volatile gasoline into a diesel engine, however, can quickly ruin it by breaking pistons, bending rods or even blowing the head right off the motor! Should you ever accidentally fill a diesel engine’s tank with gasoline, the vehicle will need to be towed and the tank and fuel system drained…a very expensive matter. 

  Tags: fuel, diesel fuel, ethanol
  Posted in: Auto Repair 101