Elimination of unstable engine crankshaft speed at idle (Fiesta 4)

If the battery cables were disconnected, the vehicle must be driven for 8 km to program all engine management system components with basic data. Otherwise, proceed as follows.



SEQUENCE OF WORKS

1. First of all, check the condition of the air hoses.

2. Check the reliability of the fuel line connections.

3. Check the electrical connectors for proper connection. Make sure there is no rust on the connector contacts. Special equipment is required for further checks.

4. Insufficient pressure in the fuel system can also cause the engine to run rough at idle. Therefore, measure the fuel pressure.