你要么先去dealer买一个Toyota正宗油箱盖换一下(ebay $25 genuine, OEM)，以下的例子换了后灯不亮了

"So, my P0401 error code seems to be the gas cap. I replaced it this morning. Drove about 50 miles in two drive cycles. Got back in the car a 3rd time and the check engine light did not come back on. I have driven it twice now with no check engine light. It was a $22 gas cap from the Toyota dealer. I don't know if that is your problem or not. The dealer service department person told me bluntly that this was not my problem and I was wasting my money buying this part. If the gas cap was the problem it would produce another a different error code. But, for my case, that doesn't appear true. I will keep driving it and we'll see."

换后，断开电瓶，踩刹车，按无电喇叭消码；再连上，开60 miles 以上（一个circle），如果换了灯还亮，第二步，去 dealer 买一个正宗 EGR valve，然后找一家车铺换，dealer 人工一般翻倍。

 

所有跟帖： 

• 非常感谢你这么详细的介绍！讲得真清楚，这些我应该会做的，不过我肉眼看不出我的的gas cap有坏的地方呢 -anmom- ♀ (0 bytes) () 10/09/2019 postreply 23:17:20

• 不客气。20年gas cap如没换过橡胶老化了。碰碰运气（ebay $25, 找配你车的年份，务必原厂件genuine或OEM） -老金工- ♂ (0 bytes) () 10/10/2019 postreply 05:34:11

• 谢谢你！麻烦你能解释一下OEM 是啥缩写吗？ -anmom- ♀ (0 bytes) () 10/10/2019 postreply 06:56:30

• Original Equipment Manufacturer，就是 genuine的意思。注意有的商铺自称品牌为“OEM”.. -老金工- ♂ (95 bytes) () 10/10/2019 postreply 07:14:07

• 谢谢你热心的行家！我明白了 -anmom- ♀ (0 bytes) () 10/10/2019 postreply 08:14:30

• 汽油盖拧上后，要听到一、俩声 "click"，否则可能会引发engine light on。 -老金工- ♂ (0 bytes) () 10/10/2019 postreply 08:32:37

• 谢谢！这车我开了近二十年从来没有听到click 声，我看车盖子上有同样的说明，但我从来拧不到这一步. 但近二十年没有事，直到最近 -anmom- ♀ (0 bytes) () 10/10/2019 postreply 09:12:12

• 还有有一次加完油我忘了油箱盖子就开走了，后来dealer那儿买了个新盖子，所以这盖子大概7，8年新 -anmom- ♀ (0 bytes) () 10/10/2019 postreply 09:14:44