06年的，跑了97,000 km 的车, check engine light popped on. The Diagnostic Trouble Codes (DTCs) were P0171, system too lean, bank 1.
此症病因甚多，先从简单的入手，清洗了Mass Air Flow Sensor, 更换了spark plugs, 不果。
进一步在网上查到 “a Toyota Technical Bulletin (TSB) issued in 2007 was found. The TSB pointed out that some 2003-2008 model year Corolla and Matrix vehicles equipped with a 1ZZ-FE engine may exhibit the problem as the result of a vacuum leak at the intake manifold.”
估计问题就在这里。新密封圈税后10元，具体更换步骤该TSB中有附。
Photo of the intake manifold with aged gasket
