1997 Buick LeSabre Q&A
1997 Buick LeSabre Question: Check Engine Light
OBD II Code P0442 means Evaporative System Malfunction, Small Leak. A very good source of information about it is found at this article in the RepairPal Encyclopedia here; http://repairpal.com/OBD-II-Code-P0442 - fernando
This is an emissions problem and better left for the pro's to diagnose rather than just changing parts and hoping for the best... Diagnostic test requires advanced scan tools and an EVAP smoke tester... ________________________________________________________________ Vehicle Application: 1997 Buick Lesabre Custom 3.8L Customer Concern: Trouble code P0442. Tests/Procedures: 1. Before starting, verify the customer did not leave the gas cap loose at any time. Also check to see if there is any rust or debris on the filler neck where the gas cap seals against. 2. Using a scanner, verify the fuel tank pressure sensor voltage reads about 1.5 volts with the gas cap loose. The voltage should be stable. 3. Check all Evaporative Emission Control System (EVAP) lines, seals and components for leaks. 4. Verify the purge solenoid allows vacuum to pass through when energized by a scanner. It should seal shut when de-energized. 5. Install a long hose on the vent solenoid. While commanding the vent solenoid on with a scanner, place the hose to your mouth and suck against the solenoid. The solenoid should be sealed shut when energized by the scanner. 6. Do this procedure with the vent solenoid several times. Vent solenoids often leak on an intermittent basis. Potential Causes: Leaking Evaporative Hose Loose Gas Cap Purge Control Valve Defective Vent Control Solenoid Tech Tips: Note: The purge solenoid is a normally closed solenoid. The vent solenoid is a normally open solenoid. Diagnostic Codes: P0442 - James Monaghan MSc.
check engine light comes on but when i shut the car off n restart it again the light stays off....
Illumination of the Check Engine Light may be the result of a loose or worn gas cap.
The cam sensor interrupter (magnet) may become demagnetized and/or fall off of the camshaft gea...
Illumination of the Check Engine Light can be caused by a loose or worn gas cap.
... ignition control module, or powertrain control module (PCM) may cause the Check Engine Light to illuminate.