Acura Coupes and Sedans 1986-1993 Repair Guide

Fuel and Engine Oil Recommendations



All Acura vehicles covered in this guide are designed to run on unleaded fuel only.

You should be careful to use quality fuels having an octane rating of 91 when measured by the R/M method, which averages "Research" and "Motor" octane ratings. Too low an octane rating will produce combustion knock, which will prove to be damaging to the engine over a long period. Always buy fuel from a reputable dealer, preferably where a regular volume is pumped so that the fuel is always fresh.

While Acura recommends the use of 91 octane or higher gasoline, your vehicle may be run on a lower octane fuel, but lower engine performance and economy will be noticed.


See Figure 1

When using engine oil, there are two types of ratings with which you should be familiar: viscosity and service (quality). There are several service ratings, resulting from tests established by the American Petroleum Institute. Use only SE rated oil or SF (for better fuel economy). SF oil passes SE requirements and also reduces fuel consumption. No other service ratings are acceptable.

Click image to see an enlarged view

Fig. Fig. 1: Engine oil viscosity chart, use this to determine the correct oil viscosity for your car

Oil can be purchased with two types of viscosity ratings, single and multi-viscosity. Oil viscosity ratings are important because oil tends to thin out at high temperatures while getting too thick and stiff at low temperatures. Single viscosity oil, designated by only one number (SAE 30), varies in viscosity or thickness, a great deal over a wide range of temperatures. The single rating number comes from the fact that the oil is basically a single, straight grade of petroleum. A multi-viscosity oil rating is given as two numbers (for example: SAE 10W-40, the W standing for winter ). Multi-viscosity oils slow changes in viscosity with temperature. These changes occur with changes in engine temperature conditions, such as cold starts versus eventual engine warm-up and operation. The double designation refers to the fact that the oil behaves like straight 10W oil at 0°F and like straight 40W oil at 200°F. The desirable advantage of multi-viscosity oil is that it can maintain adequate thickness at high engine operating temperatures (when oil tends to get too thin) while it resists the tendency to thicken at very low temperatures. A straight 30 oil gets so thick near 0°F, that the engine will usually not crank fast enough to start. Because of its versatility, a multi-viscosity oil would be the more desirable choice.

When adding oil, try to use the same brand that's in the crankcase since not all oils are completely compatible with each other.

Acura recommends the use of 5W-30 oil in all of it's engines for increased economy and engine performance.