Diagnosis By Symptom
PRELIMINARY CHECKSENGINE COOLING SYSTEM OVERHEATING
Establish what driving conditions caused the complaint. Abnormal loads on the cooling system such as the following may be the cause:
^ Prolonged idle
^ Very high ambient temperature
^ Slight tail wind at idle
^ Slow traffic
^ Traffic jams
^ High speed or steep grades
Driving techniques that avoid overheating are:
^ Idle with A/C off when temperature gauge is at end of normal range.
^ Increasing engine speed for more air flow is recommended.
TRAILER TOWING:
Consult Trailer Towing section of owners manual. Do not exceed limits.
RECENT SERVICE OR ACCIDENT REPAIR:
Determine if any recent service has been performed on vehicle that may effect cooling system. This may be:
^ Engine adjustments (incorrect timing)
^ Slipping engine accessory drive belt(s)
^ Brakes (possibly dragging)
^ Changed parts. Incorrect water pump or pump rotating in wrong direction due to belt not correctly routed
^ Reconditioned radiator or cooling system refilling (possibly under filled or air trapped in system).
NOTE: If investigation reveals none of the previous items as a cause for an engine overheating complaint, refer to COOLING SYSTEM DIAGNOSIS CHART.
These charts are to be used as a quick-reference only.
COOLING SYSTEM DIAGNOSIS CHART