Surge, Hesitation, Stall on Acceleration

SYMPTOM:
Engine hesitates or stumbles on acceleration, sometimes stalling. This condition can occur at any speed, but primarily from a stop. Vehicle may also experience a surge or rise and fall of engine speed at cruise or steady throttle.

POSSIBLE CAUSE ACTION


EGR malfunction Check Exhaust Gas Recirculation system in "Testing
flange gasket leaking, Procedures"
excessive backpressure,
loose valve


Spark timing Check Spark Controls in
"Computers And Control Systems"


Faulty canister purge Check Evaporative system in
liquid fuel in carbon canister "Testing Procedures"


Ignition timing Check Ignition Timing in "Adjustment
Procedures"


Restricted exhaust system Check Three Way Catalytic Converter System in
"Testing Procedure" in Emissions


Poor or contaminated fuel Recommend higher grade fuel