Altitude correction switch

Due to lower air pressure, the engine mixture will be richer at higher altitudes. The function of the altitude switch is to regulate fuel mixture at higher elevations. The altitude switch closes at 1,000 meters (3,280 feet) above sea level. This leans the fuel mixture by 0.5% to 1.0%.

^ The altitude correction switch (B) is located under the driver seat.

— To test altitude switch, remove driver seat as described in 720 Seats.

— Connect ohmmeter across switch terminals. There should be no continuity. If testing above 1,000 meters (3,280 ft.), there should be continuity.

— With engine running at operating temperature, check CO level.

— Remove harness plug from altitude correction box. CO value should not change. Bridge harness terminals. CO should drop 0.5%-1.0%.

Evaporative emission control system

5. Carbon canister

6. Air filter housing

7. Engine fan

1. Fuel tank

2. Expansion chamber

3. Restrictor

4. Evaporation chamber

5. Carbon canister

6. Air filter housing

7. Engine fan

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