Idle Speed Adjustment - Rough Idle: Overview

S.L 102C-7
09/30/82

SUBJECT: IDLE SPEED ON FUEL INJECTED VEHICLES

VEHICLES: ALL FIAT 1500cc ENGINE MODELS WITH FUEL INJECTION

SERVICE INFORMATION:

The proper procedure for setting idle speed on fuel injected vehicles listed below should be performed during the Pre-Delivery Inspection of a new vehicle and whenever a rough idle condition is experienced.





IDLE SPEED ADJUSTMENT PROCEDURE

1. Connect tachometer. Run engine until it reaches normal operating temperature.
2. On cars with automatic transmission, apply hand brake and - Place gearshift lever in "D".
3. Turn idle speed adjustment screw all the way in.
4. Loosen the throttle plate switch.





5. Adjust accelerator linkage stop screw to obtain 100 RPM below idle speed specified on the E.P.A. Conformity Tag in the engine compartment.
6. Adjust throttle plate switch for "idle" and "full" throttle contacts. Refer to Service Manual or Fuel Injection Diagnosis Book.






7. Check accelerator cable adjustment by pulling back lightly on the accelerator transfer rod and checking for approximately 1 mm movement of rod before the throttle plate linkage moves.





8. If necessary adjust the accelerator cable as follows;

^ Loosen the locknut on the accelerator cable rod end.
^ Disconnect the cable rod end for the transfer rod.
^ Adjust the rod end to obtain the 1 mm movement. Connect the rod end to the transfer rod and tighten the locknut.

CAUTION
Be sure not to adjust rod end out too far.





9. Adjust idle speed adjustment screw to obtain the correct - RPM as specified on the E.P.A. Conformity Tag.
10. Hold adjustment screw and tighten the locknut.