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Poor Idle Problems -Check Wire Loom Near Valve Cover (VLK0303AP)

WARNING: This page is about the Jetta GL, 4D Sedan, 1.6 F, which is a different variant/trim than selected.
Publication date: 1998-08-01
Reference number: VLK0303AP

POOR IDLE PROBLEMS -CHECK WIRE LOOM NEAR VALVE COVER

POOR IDLE PROBLEMS -CHECK WIRE LOOM NEAR VALVE COVER

TECHNICAL INFORMATION TIP

Reference Number(s): VLK0303AP, Date of Issue:  August 1998

IDLES PROBLEMS

YEAR(S): 1991

MANUFACTURER: Volkswagon

MODEL(S): Jetta

DATE OF ISSUE: August 1998

ISSUE & TIP

Erratic or poor idle problems on 1991 VW Jettas may be cause by a damaged wiring harness. The wires to the IAC motor are routed inside the harness, near where the grounds attach to the cylinder head assembly. A leaking valve cover gasket will allow the harness to become saturated with oil, which eventually creates the potential for damage to the wires inside the loom. Because of this, the insulation on the IAC wires will crack - causing an intermittent short. When repairing the harness, it is a good idea to add 4-6 inches to each wire so they can be routed further away from the valve cover.

Courtesy of Import Service Magazine

with thanks to:

Loren V. Kiner

Imperial Car and Truck

Henderson, Nevada

REFERENCE NUMBER

VLK0303AP

NOTE: This information has been obtained from sources generally believed to be reliable. Use your own judgment before relying on this data. Neither the suppliers of these Technical Information Tips, nor lemon-25 Repair Information Company, LLC, guarantees or assumes responsibility for data accuracy or completeness, nor is liability assumed by the suppliers of these Technical Information Tips or lemon-25 Repair Information Company, LLC, for any claims or damages resulting from the use of this information.