Hard Starting, Runs Rough
07.3-89042 A. Engine is Difficult to Start (Long Cranking All CIS-E Engines Revised 1/90 4/89Time)
B. Engine does Not Fire on All Cylinders (Runs Rough)
A. Engine is Difficult to Start (Long Cranking Time)
All Engines with CIS-E:
A cranking time of four seconds is normal with the CIS-E injection system. Do not depress the accelerator pedal while cranking.
1. Engines 102, 103 (see also DD15-89043 re; spark plug heat range)
Cause:
If no failure has been determined during all normal engine tests, the current (mA) should be checked at the electrohydraulic actuator while cranking the engine. If a negative current (approx. -40 to -60 mA) is measured, the CIS-E control unit recognizes deceleration shutoff.
Remedy:
Install a ignition control unit manufactured by Siemens.
2. Engine 103
Remedy:
Check if the correct cold start valve, Part No. 102 070 01 46, spark plugs Bosch H 9 DC/DCO Beru 14 K-9 DU/DUO and fuel pump relay with cold start valve activation up to + 60°C is installed.
Fuel Pump Relay with Cold Start Valve Activation
3. Engines 102, 103
See DD05-89101 re; intake valves pulling through valve seats, and jammed hydraulic compensating elements.
B. Engine Does Not Fire on All Cylinders (Runs Rough)
Cause:
1. Fuel injection valves are leaking.
2. Rest position of airflow sensor plate not as specified, fuel distributor detective.
Remedy:
1. Test fuel injection valves, replace if necessary.
2. Check rest position of airflow sensor plate. Remove fuel injection lines at fuel injection valves and fuel distributor. Unplug fuel pump relay and bridge circuits 30 and 87. With the airflow sensor plate at rest position, no fuel should come out of the fuel line connections, if required test fuel distributor or replace if necessary.
When depressing the airflow sensor plate, fuel should come out of all fuel line connections simultaneously, replace fuel distributor if necessary.