3.3 CIS-E and CIS-E Motronic Troubleshooting

This information applies specifically to the CIS-E fuel injection system, and the fuel injection functions of the CIS-E Motronic engine management system. The oxygen sensor system and the CIS-E Motronic EGR system (California cars only) are covered in EXHAUST SYSTEM AND EMISSION CONTROLS. For information on troubleshooting the other fuel systems, see 3.2 CIS Troubleshooting or 3.5 Digifant II and Digifant I Troubleshooting.

CIS-E Motronic is also equipped with built-in fault diagnosis circuitry which can detect and report component faults electronically. The first step in troubleshooting CIS-E Motronic should be to read the fault codes which are stored in the Motronic control unit memory. For more information, see 3.4 CIS-E Motronic Fault Diagnosis.

The basic factors of engine idle speed, ignition timing, and idle mixture are critical, as they affect all other aspects of fuel injection performance. Before making any other adjustments to the system, make certain that these factors are within specifications. See 6.3 Idle Speed, 6.7 Idle Specifications, and IGNITION.

Table b lists symptoms of CIS-E and CIS-E Motronic fuel system problems, their probable causes, and suggested corrective actions. The boldface numbers in the corrective action column indicate the heading in this section of the manual where the applicable test and repair procedures are found.

Table b. CIS-E and CIS-E Motronic Troubleshooting