Fuel Injected & Prelude Carbureted

Disconnect coolant temperature (TW) sensor connector. Measure resistance across sensor terminals. Resistance should be less than 1000 ohms if coolant temperature is greater than 100°F (38°C).
Start engine. Allow engine to reach operating temperature (cooling fan comes on). Measure resistance across sensor terminals. Resistance should be 200-400 ohms. If sensor values are not within specification, replace thermosensor.

Fig 1: EGR System (Accord - Carbureted)

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 2: EGR System (Accord - EFI)

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 3: EGR System (Civic CRX HF - EFI)

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 4: EGR System (Prelude - EFI)

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 5: EGR System (Prelude - Carbureted)

Courtesy of AMERICAN HONDA MOTOR CO., INC.