Is there a way to find a code for the check engine light instead of taking it to a shop? If so what do you need to check it.
My '93 doesn't have a check engine light, but the CFI Control Module still stores DTC codes and I can retrieve them using one of the homemade LED testers that has been discussed on this site.
Since yours has the check engine light then it probably has the built-in LED mounted in front of the battery. Press button for 2 to 4 seconds, note readout.
1 flash = No malfunction in system
2= Throttle position switch, wide open throttle contact
3= Engine coolant temperature sensor
4= Air flow sensor potentiometer
5= Heated oxygen sensor
6= not assigned
7= TD signal
8= Barometric pressure sensor
9= Electrohydraulic actuator
10= Throttle position switch, closed throttle position contact
12= Exhaust gas recirculation temperature sensor (California models only)
Info. from manual:
"The CFI control module monitors all the exhaust components of the CFI injection system and the exhaust gas recirculation. Malfunctions caused
by an open circuit or failure of one of these components are indicated by the malfunction indicator lamp in the “CHECK ENGINE” instrument cluster and simultaneously stored in the CFI control module.
A diagnostic connector (X92) with non-locking switch (2) and LED (4) is provided for this purpose on the right of the component compartment partition wall. When the nonlocking switch is pressed (ignition: ON) for
between 2 and 4 seconds, the flashing DTC output is initiated and the fault path indicated by the number of flashes.
After completion of the flashing DTC output, the LED shows a steady light. If the non-locking switch is again pressed for between 2 and 4
seconds, a further fault path can be indicated if it exists. If no further fault code is detected, the CFI control module switches over to on/off ratio
Erasing flashing DTCs. Once a fault has been rectified without having
disconnected the CFI control module, the flashing DTC output displayed must be erased as follows:
When the flashing DTC output is displayed, wait 2 seconds before pressing the nonlocking switch for 6 - 8 seconds.
Each flashing DTC output displayed must be erased individually.
The non-locking switch and LED have been developed to enable customers and non-MB dealers to specifically pinpoint the fault path with “on board means” in conformity with legal requirements. An impulse counter scan tool
which indicates the stored fault(s) on a digital display has been developed for MB workshop personnel (see DTC output to diagnostic connector)."