Wheels/Tires - Slow Leaks Over Extended Time Period
TECHNICALBulletin No.: 09-03-10-002
Date: February 19, 2009
Subject:
Possible Slow Air Leak From Tire Over Extended Periods (Replace Tire Pressure Monitor (TPM) Sensor)
Models:
2008 Saturn Astra
2009 Saturn Astra (Canada Only)
Condition
Some customers may comment that, over an extended period of time, one or more tires may consistently lose air at a rate faster than the other tires. This loss of air is correctly indicated by the tire pressure monitoring system.
Upon inspection of the tire in question, no road hazards may be found and submerging the tire in a water tank does not indicate an obvious leak.
Cause
This condition may be caused by the TPM sensor air seal being improperly seated to the mounting hole in the wheel, resulting in distorting or pinching of the air seal, as shown above.
Correction
Note
This type of slow leak may be difficult to diagnose. Time and patience are required to properly identify the source.
Diagnose this issue by inflating the tire to the recommended pressure and submerging the affected wheel and tire assembly in a water tank. A leak of this nature will be very small and may take a longer period of submersion before an air bubble will form. Confirm that the air leak is from the general area of the valve stem. If confirmed, replace the sensor. Refer to Tire Pressure Indicator Sensor Replacement in SI.
Important:
The air seal at the base of the sensor is conical in shape as shown in the photo. This shape provides effective air sealing and helps to guide the seal into the wheel hole. Observe that the seal is installed evenly when replacing the replacement TPM sensor.
Parts Information
Warranty Information
Disclaimer