Erratic distributor dwell-V8i

ERRATIC DISTRIBUTOR DWELL-V8I

Model

Range Rover V8i Discovery V8i

Affected vehicles

All V8 engine EFi derivatives prior to LH 639964 and LJ 064773

Date

1994-05-04

Reference

04/05/94

Bulletin text

Erratic Distributor Dwell

MODEL AFFECTED VEHICLES

Range Rover V8i All V8 engine EFi derivatives prior to LH 639964 and LJ Discovery V8i 064773

DETAIL

During distributor dwell checks with a dwell meter, you may observe erratic ignition dwell readings at engine speeds of between 1000 and 3000 rpm, most likely to occurr between 1500 and 2500 rpm.

The erratic dwell is generally an extreme and downward change in the dwell period. Radio frquency noise generated from the tip of the ignition rotor arm interfers with the coil current control circuitry in the ignition module which results in erratic dwell.

This sysmptom is cured by installing a new design of rotor arm which has a coating of silicon on the rotor arm tip. The new rotor arm was introduced from the above VIN numbers and can be fitted to previous models.

ACTION REQUIRED

Upon evidence of erratic dwell fit the new rotor arm. DO NOT REPLACE THE IGNITION MODULE IF ERRATIC DWELL IS EVIDENT.

PARTS INFORMATION

STC 1857 Rotor arm replaces RTC 6629

PROCEDURE

Refer to section 86 of the workshop manual for fitting instructions.

04/05/94

86/08/94/EN

WARRANTY

Normal warranty policy and procedures apply

COMP. CODE

7A6U

SRO

86.35.16 Rotor arm renew 00.10 hour