Had this light come on yesterday. I park my car in a heated garage (17C or 65F temperature).

I then went out and the car was parked outside for an hour (0C or 32F temperature).

When I left the light came on. Gas cap was tight. Drove to my new destination which took 30 minutes and parked the car outside for 12 minutes. When I restarted the car, the message was gone.

I suspect the temperature differences caused the fuel to contract and decrease in volume, decreasing the gas tank pressure and tricking the computer into thinking that the gas cap was off.

Anyone have any other explanations? This is the first time this has happened.

 

There are several reasons for a tighten fuel cap warning ...
1. Loose or cracked cap
2. Faulty ruber seal
3. Gross leak
4. Vent Solenoid and or the fuse to such
5. Water / air vapor in gas and often Ethanol related

Check the code to see if more specific.
You are right its all a computer sense thing
but temperature alone is doubtfull unless it pulls air.

 

I have found that a drastic change in atmospheric pressure causes my light to come on. After I drive for a bit, shut off the ignition and restart, the light is off.

 

Thanks Jeff. Yes, I attribute this to pressure difference due to a dramatic temperature drop.

My vehicle was parked in a heated garage (20C or 68F). In then drove outside and left the car parked in 0C or 32F weather. My theory is the reduced temperature lowered the gas tank pressure fooling the computer into thinking the gas cap was off.

I opened the gas cap to let the pressure equalize, turned off the engine for 30 minutes and the light never came on again.

 

I currently own 2 Acura's and did own a 2007 TL that I sold. I have had the warning on all three and none of EL's items have made a difference. I was told it must just be that Acura has set the sensors to sensitive. Another words they don't have a clue after replacing everything that can be replaced. If you look around you'll find lots of complaints about this problem.