Examination
1. If a malfunction occurs in the engine management system, first check the reliability of the docking of all electrical connectors of the system and the absence of corrosion in them. Make sure the problem is not the result of poor maintenance. It is necessary to check the cleanliness of the air filter element, the condition of the spark plugs, the interelectrode gaps in them and the compression in the engine cylinders. Also check the engine vent hoses for dirt or damage. See chapters for more information 1A, 2A and 5 B.
2. If these checks do not uncover the cause of the problem, take the vehicle to a Peugeot/Citroen dealer or a qualified engine management system diagnostician. Next to the passenger compartment fuse box is a diagnostic socket that can be connected to a DTC reader or other special electronic test equipment (pic. 11.2). Test equipment can «request» electronic control unit (BEU) engine management systems (electronic control units of other vehicle systems) and provides access to the internal fault memory of the BEU for reading fault codes. Using such equipment, it is possible to quickly and easily identify the causes of a malfunction, even if they appear only from time to time. Checking all elements of the system separately while trying to identify a malfunction by elimination is a rather lengthy procedure, and it is unlikely that it will be fruitful (especially if the problem doesn't always show up). In addition, this entails a high degree of risk of damage to the internal elements of the electronic control units.
Pic. 11.2. Diagnostic connector (marked with an arrow) located next to the passenger compartment fuse box
Adjustment
3. An experienced non-professional mechanic, with sufficient experience and with the necessary equipment, is able to check the CO level in the exhaust gases and determine the idle speed of the crankshaft. If these parameters are not correct and require adjustment, you should contact your dealer or another specialist who has the appropriate equipment to diagnose the car. Neither the composition of the air-fuel mixture (CO content in exhaust gases), nor the idle speed can be manually adjusted. Unsatisfactory test results indicate a malfunction in the engine management system.