Hesitation, Sag, Stumble

Definition: Momentary lack of response, as the accelerator is pushed down, can occur at all vehicle speeds. Usually, most severe, when first trying to make the vehicle move, as from a stop sign. May cause the engine to stall, if severe enough.
- Perform careful visual (physical) check as described in Before Starting. - Important Preliminary Checks
- CHECK:
- Fuel pressure. See CHART A-6. Chart A-6 Fuel System Pressure Test
- Water contaminated fuel.
- Ignition timing. See "Vehicle Emission Control Information" label.
- For correct PROM / Cal Pak
- TPS for binding or sticking.
- Generator output voltage. Repair if less than 9 or more than 16 volts.
- For open HEI ground, CKT 453.
- Canister purge system for proper operation.
- EGR valve operation.