If you have rough or erratic engine idling:

1. Inspect - AIR FILTER - Restricted or clogged air filter.
2. Inspect - FUEL FILTER - Clogged or dirty fuel filter
3. Inspect - WIRESET - Damaged, worn, or deteriorating spark plug or coil wire(s).
4. Inspect - SPARK PLUG - Fouled, damaged or broken spark plug(s).
5. Inspect - PCV VALVE - Plugged or damaged PCV valve.
6. Inspect - DISTRIBUTOR CAP - Loose or cracked distributor cap
7. Inspect - CARBURETOR FLOAT - Improperly adjusted/saturated or damaged carburetor float.
8. Inspect - CHOKE PULLOFF - Worn, defective, or faulty choke pull-off(s).
9. Inspect - CHOKE THERMOSTAT - Stuck or improperly functioning choke thermostat.
10. Inspect - AIR CHARGE SENSOR - Damaged or faulty air charge sensor or air charge sensor circuit.
11. Inspect - AIR CLEANER TEMPERATURE SENSOR - Damaged or faulty air cleaner temperature sensor or air cleaner temperature sensor circuit.
12. Inspect - BAROMETRIC PRESSURE SENSOR - Damaged or faulty barometric pressure sensor or barometric pressure sensor circuit.
13. Inspect - FUEL INJECTOR COLD START VALVE - Faulty cold start valve or circuit.
14. Inspect - FUEL INJECTOR PRESSURE REGULATOR - Faulty fuel injector pressure regulator or circuit.
15. Inspect - CARBURETOR/FUEL INJECTION GSK - Deteriorated or faulty carburetor/throttle valve mounting gasket.
16. Inspect - IDLE AIR CONTROL VALVE - Damaged, loose, or faulty idle air control valve.
17. Inspect - IDLE SPEED CONTROL ACTUATOR - Damaged, loose, or faulty idle speed actuator.
18. Inspect - MAP SENSOR - Improperly connected or faulty M.A.P. sensor.
19. Inspect - MASS AIR FLOW SENSOR - Improperly connected or faulty mass air flow sensor.
20. Inspect - THROTTLE POSITION SENSOR - Faulty throttle position sensor or throttle position sensor circuit.
21. Inspect - TIMING SET - Slipped timing chain or worn timing gear(s).
22. Inspect - FUEL PUMP - Improperly functioning fuel pump or circuits.
23. Inspect - FUEL TANK - Contaminated fuel from rusted or deteriorated fuel tank.
24. Inspect - FUEL INJECTOR - Plugged, dirty or poorly connected fuel injector.
25. Inspect - EGR VALVE - Clogged, dirty or improperly functioning or defective EGR valve.
26. Inspect - DISTRIBUTOR - Worn, loose or incorrectly adjusted distributor.
27. Inspect - CAMSHAFT - Worn or scored camshaft lobes may affect proper fuel intake, compression, combustion and exhaust.