FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Diagnostic Trouble Code (DTC) Information






Diagnostic trouble code (DTC) information ECM-984A

Condition




Diagnostic trouble code (DTC) ECM-984A is stored if the engine control module (ECM) registers an internal fault indicating that the calculated load signals for the normal engine control functions are lower than calculated by the internal monitoring functions. The diagnostic trouble code (DTC) is diagnosed with the engine running and at an engine speed (RPM) of more than 1000 rpm.

Substitute value
The engine speed (RPM) and torque are limited to a calculated normal operating range.

Possible source
- Blocked exhaust system.
- Blocked intake system.
- Air leakage in the intake system.
- Defective engine control module (ECM).

Fault symptom[s]
- Maximum engine speed (RPM) too low
- Cruise control does not function at all
- Uneven idle
- Malfunction indicator lamp (MIL) lit.