Test and Adjustment Jobs

Listing of Test Steps

1 Test equipment
connect/disconnect.
2 CFI control module on-off ratio test (Ignition: ON)
perform. Reading Diagnostic Trouble Codes
3 CFI control module on-off ratio test (Engine: closed throttle)
perform (wait until readout display oscillates). Reading Diagnostic Trouble Codes
4 Diagnsotic trouble code read-out of CFI control module (Ignition: ON).
perform. Reading Diagnostic Trouble Codes
5 Engine systems (MAS) control module (N16) diagnostic trouble code read-out (Ignition: ON)
perform Reading Diagnostic Trouble Codes
6 Ignition control module diagnostic trouble code read-out (at engine rpm)
perform. Reading Diagnostic Trouble Codes
7 Air filter
remove and install.
8.0 Linkage rods
check throttle valve for free movement and condition. Lubricate bearings, slotted lever and ball sockets.
8.1 Closed throttle (idle) contact
check, adjust.
8.2 Wide open throttle contact
check using accelerator pedal, adjust.
9 Control pressure cable
check, adjust.
10 Cruise control (without ASR)
check, adjust.
11 Engine coolant level
check, correct.
12 Engine oil level
check, observe condition of oil.
13 Voltage at ignition coils
check. Test and Adjustment Data [Specifications]
14 Ignition timing and vacuum advance
check. Test and Adjustment Data [Specifications]
15 Oscilloscope patterns
evaluate. Non-Trouble Code Procedures (Engine Analyzer Tests & Values)
16 Engine oil temperature
approximately 80 °C.
17 Intake system
check for leakage.
18 Closed throttle (idle) speed
check.
19 Lambda control system
test.
20 Closed throttle under load
check.

Connection Diagrams

Test Equipment - Engine 104:

Test Equipment - Engine 119:

Impulse Counter & On/Off Ratio Tester - Engine 104, 119:

Connection Chart For Test Equipment without Diagnostic Adaptor for Two Circuit Ignition Systems

Notes regarding on/off ratio check using on/off ratio tester:
The operation of the Lambda control can be tested by checking the on/off ratio. In addition, any malfunctions that exist momentarily can be recognized. The tests distinguish between malfunctions that occur with the ignition ON or with the engine at idle.

The on/off ratio can be checked using the on/off ratio tester or engine analyzer. An on/off ratio of 50% indicates that all input signals are OK, but Lambda control is not functioning. A varying on/off ratio indicates that the Lambda control is functioning correctly. On/off ratios from 10% to 95% are each assigned a specific malfunction (see Computers and Control Systems, Testing and Inspection). After testing the on/off ratio, a diagnostic trouble code (DTC) readout using the impulse counter scan tool must always be performed.

Notes regarding diagnostic trouble code (OTC) readout using the Impulse counter scan tool:

NOTE: When diagnosing engine running complaints, or when the CHECK-ENGINE lamp is illuminated, the DTC memory should be read out and the DTC's noted before any repairs are attempted. This will ensure that the technician can differentiate between actual malfunctions and "simulated malfunctions," since testing done on a running engine will cause malfunctions to be stored that were caused by a simulation or a disconnected circuit.
When testing is completed, the DTC memory of the CFI and Ignition control modules and the Engine systems control module (MAS) must be cleared.

1. Connect impulse counter scan tool according to diagram.
The LED U-Batt" should come on. If not, check the following:
a) Voltage Supply.
b) Impulse counter scan tool fuse.

2. DTC memory readout
a) Ignition: ON.
b) Push start button for 2-4 seconds.
c) Read and record DTC readout.
d) Push start buffon again.
e) Read and record DTC readout.
Repeats steps d) and e) until the first DTC readout reappears.

3. Clearing DTC memory

NOTE: The clearing process must occur within 20 seconds after the DTC readout.

a) Push start button 2-4 seconds (Impulse display appears).
b) After a waiting period of 3 seconds, push the start buffon for 6-8 seconds which will erase the previously displayed DTC.
c) Erase each DTC separately.

Special Tools