1993 Civic DX
 

Hi Everyone, I recently got this car with 222K on it for my daily driver. I have done all of the general maintenance on it (spark plugs, wires, rotor cap/button, fuel filter, timing belt, air filter, fuel system cleaner, oil change ect). I am going to check the PCV valve soon as well. The car does not burn oil or leak anything as well. Since the car did not come with the owners manuel, I don't know what type of octane to use. I am assuming its 87, but since it has many miles on it should I switch to something higher (1.5L motor non-vtec)? It does tick a little bit and any sugeestions would be great. Thanks!

Ticking noise could be the valve adjustment.

They are designed for 87 octane.

We run 87 octane in our 90 Civic DX. I pulled the spark plugs the other day & found plugs with a .075 gap & Autolites on top of that. I couldn't get NGKs or Denso's so I settled for a standard Bosch plug. I'm hoping for a gas mileage improvement.

87. anything else for that motor and you are wasting money.