Vanden Plas (X300) L6-4.0L (AJ16) (1996)
Technical Service Bulletin # 05_1-15
Date: 960401
Engine Performance - Intermittent High Idle
05.1-15
DATE
4/96
Sedan Range
MODEL
1995-96 MY
Sedan Range
VIN
720001-775319
Intermittent High Idle - Replace Throttle Return Spring
ISSUE:
Some 1995-96 MY 4.0L Sedan Range 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 Sedan Range 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 Reverse or Drive 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 (Section 5.1.7 in the XJ6-XJ12 Vehicle Service Manual). If the condition is still present, replace the throttle spring with a stronger spring as
described in the appropriate procedure.
Replacing Throttle Spring - Normally Aspirated Engines
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.