Testing & Diagnosis: Notes

NOTE: Due to the complexity of the EEC-III system, full testing cannot be done unless a special tester is used. Instructions for testing come with the tester, which is available from Owatonna Tool Co. However, some checks can be made using regular shop equipment. These checks are outlined in the following procedures:

No repairs or adjustments can be made to the ECA components. If diagnosis shows Processor or Calibration units are not functioning properly, they must be replaced.
Shorting the wiring harness across a solenoid valve can burn out circuitry in the ECA that controls the solenoid valve actuator.
The EEC system contains transistors which CANNOT tolerate excessive voltage surges or transient voltage. Never try to jump-start the vehicle with 24 volts.
Fuel supply lines will remain pressurized for long periods of time after key is turned off. This pressure must be relieved before servicing fuel system by removing air cleaner and cautiously depressing pin in Schrader valve on fuel charging main body. This will expel fuel into throttle body.