Hombre XS Space Cab 2WD L4-2.2L CPC (1999)
Auxiliary Air Valve (Idle Speed): Customer Interest
Engine Controls - Closed Throttle Hissing Noise
TSB SBO3-03-S003
Idle Air Control Valve (IACV) Hissing Noise (Replace the IACV)
ISSUE DATE: MAY 2003
Affected Vehicles
1999-2000 Hombre (TH) with 2.2L Engine.
Service Information
Condition:
Some owners may comment on a hiss noise at closed throttle only. This may sound similar to a belt noise or a power steering pump noise when it is cold.
The noise source may be identified by using a hose or a stethoscope and listening in the Idle Air Control Valve (IACV) area. This noise is most
noticeable after releasing the throttle at cold idle (1050-1200 RPM). The noise is related to the IACV pintle position, typically around 70 counts.
Possible Cause:
The condition may be caused when air moves past the shoulder of the IACV pintle. The current profile imparts a disturbance to the airflow, which
propagates into the intake manifold. As a result, the manifold walls vibrate causing the noise. To identify if the noise is due to the IACV, connect a Tech
2 to a warm engine and adjust the idle from 1050 RPM to 1200 RPM. The noise will be revealed if the IACV pintle is of the old design.
Correction:
Replace the IACV with P/N 8-12482-707-0.
Service Procedure
Refer to the Engine Controls sub-section of Engine in the appropriate Service Manual for IACV replacement.
Parts Information
Warranty Claim Information
Use the labor operations shown.
Labor Time includes administrative time allowance.
Disclaimer
