940 L4-2320cc 2.3L SOHC VIN 83 B230FD (1993)
Connecting CO Meter
4.
Connect a CO-meter to the test port in the exhaust system. Use VOLVO tool #5410 or equivalent to access the test port.
5.
Run engine to operating temperature.
6.
Check CO content at idle.
CO should be:
0.4 - 0.8%
Disconnecting Oxygen Sensor Lead
7.
Separate the oxygen sensor (lambda sond) connector.
a. If the CO level drops below 0.4%, check intake system for air leaks and repair as necessary.
b. If the CO level rises above 0.8%, check fuel injectors for fuel leaks and check fuel system pressure (see FUEL SYSTEMS), repair as
necessary.
Checking ECU
8.
Ground lead to ECU.
a. The CO content should now rise, indicating correct operation of the ECU and wiring.
b. If the CO content does not rise, fault lies in the wiring or the ECU. Check wiring and repair as needed.
