General description
1. The coast down valve is installed on vehicles delivered to the UK with a manual transmission. Its function is to supply the intake manifold with additional air during braking in order to reduce HC and CO emissions.
2. Malfunction of this system can cause rough idle, high idle and ignition off operation.
Examination
3. Checking the economy system when coasting is described in Section 1, Chapter 39.
Replacement Parts
Coasting lean valve
4. Remove the air filter and disconnect a negative wire from the accumulator.
5. Remove the screws that secure the valve to the carburetor. Disconnect the electrical wiring from the valve and remove it (photo). Remove the O-ring.
Removing the coast down lean valve (with carburetor removed)
6. Install the new valve in reverse order.
Idle switch
7. Remove the air filter and disconnect the negative battery cable.
8. Remove the screws securing the idle switch to the carburetor. Disconnect the electrical wiring from the switch and remove it.
9. Install the new switch in reverse order. Before installing the air filter, check the switch setting as described in Section 1, Chapter 39.
Control block
10. See Chapter 8.