Surges and/or Chuggle

Definition: Engine power variation under steady throttle or cruise. Feels like the car speeds up and slows down with no change in the accelerator pedal.
^ Be sure driver understands Transmission Converter Clutch and A/C compressor operation in Owner's Manual.
^ Perform careful visual inspection as described at start of Section B.
^ CHECK:
- Loose or leaking air duct between MAF sensor and throttle body.
- Generator output voltage. Repair if less than 9 or more than 16 volts.
- If a "SCAN" tool is available which plugs in to the ALCL connector, make sure reading of VSS matches vehicle speedometer. See Introduction explaining "SCAN" tool positions.
- EGR - There should be no EGR at idle. See
CHART C-7.
- EGR filter for being plugged .
- Vacuum lines for kinks or leaks.
- Ignition timing. See Emission Control Information label.
- In-line fuel filter. Replace if dirty or plugged.
- Fuel pressure while condition exists. See CHART A-7.
^ Inspect Oxygen sensor for silicon contamination from fuel, or use of improper RTV sealant. The sensor may have a white, powdery coating and result in a high but false signal voltage (rich exhaust indication). The ECM will then reduce the amount of fuel delivered to the engine, causing a severe driveability problem.
^ Remove spark plugs. Check for cracks, wear, improper gap, burned electrodes, or heavy deposits. Also check condition of distributor cap, rotor, and spark plug wires.