Fuel System - Intermittent High Idle
19-38DATE
4/96
MODEL
XJS (4.0L)
1995-96 MY
Intermittent High Idle - Replace Throttle Return Spring
ISSUE:
Some 1995-96 MY 4.0L XJS vehicles may occasionally exhibit a higher than target idle speed under certain driving conditions.
This condition may occur under city driving conditions when there is no pressure on the accelerator pedal.
ACTION:
In case of a customer complaint of intermittent high idle on 1995-96 MY 4.0L XJS vehicles within the above VIN range, verify the complaint by checking whether the engine returns to the target idle speed when the throttle is released:
700 rpm* in Park/Neutral; 580 rpm* in Drive or Reverse ranges.
* At coolant temperatures less than 86°F (30°C) idle speed +/- 30 rpm; at coolant temperatures greater than 86°F (30°C) idle speed +/- 20 rpm.
If a condition of high idle speed is confirmed, check the throttle pedal for obstructions, check that the throttle cable moves freely, and check the throttle cable adjustment. If the condition is still present, replace the throttle spring with a stronger spring as described in the following procedure.
REPLACING THROTTLE SPRING
1. Disconnect the inner accelerator cable from the throttle body.
2. Remove the cruise control linkage pin and circlip.
3. After removing the three torx screws, carefully remove the throttle assembly cap from the pedestal.
NOTE:
It is important to note that the straight extension of the throttle return spring is against the post next to the idle speed control valve. The straight extension of the spring must rest against this post only.
4. Unhook the throttle return spring (Illustration 1), from the throttle shaft actuator and then remove the spring and sleeve from the shaft.
5. Remove the sleeve from the spring and discard the spring.
6. Insert the sleeve into the replacement spring, install the sleeve and the spring on the throttle shaft and hook the spring on the actuator.
NOTE:
The revised throttle return spring must be pre-loaded by rotating the straight extension one full turn counterclockwise until it can be installed in the same position against the post next to the idle speed control valve, as the original spring.
6. Carefully install the cap on the throttle assembly noting the lever location.
7. Reconnect the cruise control linkage.
8. Reconnect the accelerator cable to the throttle body assembly.
9. Check the operation of the throttle body.
PARTS INFORMATION:
WARRANTY INFORMATION: