Hesitation, Stumble

DEFINITION:

Momentary lack of response as the accelerator is pushed down. Can occur at all car speeds. Usually most severe when driving away from a stop. May cause the engine to stall if severe enough.

Visually Check:
- Vacuum hoses for splits, kinks and proper connections, as shown on vacuum hose routing diagram label.
- Ignition wires for cracking, hardness, and proper connections, at both distributor and spark plugs.
- Wiring for proper connections, pinches and cuts.

Check float level using external float gage.

Check carburetor accelerator pump operation.

Check EGR valve operation.

Check PCV valve and hose.

Check TPS adjustment.

Check canister purge system for proper operation.

Check for open ignition coil ground and for intermittent ECM ground.

Check ignition timing. See Vehicle Emission Control Information label.

Poor or contaminated gasoline, suggest owner try different brand.

Note: Cold engine only, check the following for sticking or faulty operation.

- Check for proper operation of TCA. Make sure hot air tube is connected to air cleaner.
- Check carburetor choke, including vacuum break, throttle linkage and fast idle cam.