I met my wife for dinner last night after work. When we were finished eating, I started the TSX, started to head home and my phone rang. As I was trying to navigate the parking lot and answer my phone, I noticed the yellow light on my dash wasn't reminding me to put my seatbelt on; rather it was the "tighten fuel cap" message. (First time I've seen this, owned the car for about 9 mos now). I picked up the phone, and my wife says, "Is there any reason why my car (2008 Odyssey) is telling me to tighten the fuel cap?" What are the chances?

The TSX was locked when we were eating, and when I got home the gas cap was fine. I filled up 3 days ago, and have ~1/2 a tank left. My wife's situation was similar: around 1/2 a tank left, filled up several days ago, the vehicle was locked and the odyssey has a fuel door release inside so you can't open it (easily) without getting into the vehicle. Both cars ran fine on the way home. I hooked up my scanner when we got home to both cars, and both said there was no MIL on; however, erasing the codes (even though it thought there weren't any codes to erase) cleared the message on both cars. I'll keep an eye on them, but I'm weirded out by this.

 

OK, I would ask you what are the common denominators between the two vehicles? The answer is the weather. Most likely the temperature that night was cooler or the barometer pressure was much different, perhaps before or after a storm and caused this problem. How to fix this problem? It's not really a problem, so nothing to fix. Just a weird coincidence due to the weather. Go drive your car and be happy you don't have bigger problems.