This has happened twice, now.

I'm driving and suddenly an error message comes on the screen saying Fuel Cap Loose / Open. If I stop open up the Fuel Cap and screw it shut it will go away, but then the Check Engine light comes on. When it first happened, the Check Engine light stayed on for a couple of days and then one day it was gone. I just got the Fuel Cap message today, followed by the Check Engine light. I will have to wait and see if the Check Engine light goes away or not.

Any thoughts?

To clarify:

The fuel cap is not loose. This error message sets off the check engine light which then goes away after a couple of days.

It is normal for a defective or not properly seated cap to throw a check engine light. At the age of your car a bad cap isn’t unusual. I suggest following George and Kira’s suggestions for testing your existing cap. A replacement cap is probably the cheapest solution to your issue. If you’re curious, getting the code read will tell you exactly what your problem is.
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Will I buy another Volvo??? We'll see....

If the gas cap seal is suspected, one step short of buying a new cap is to try a new gas cap seal. Remove the old damaged seal and replace with a new seal, rubber or Viton. Have purchased these seals from ipd.

Thanks!

Maybe your cap is bad? I would consider trying a new cap.

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Will I buy another Volvo??? We'll see....

Thoughts, you say?
1) People try placing a gas cap in a plastic grocery bag (to act as a gasket) to see if the problem will go away. Buy a new cap if it at all effects the recurrence of the problem.

2) Some people have posted using a smear of silicone grease to, again, seal the gas cap better. If that halts or slows the recurrence of a problem, get a new cap.

3) When the problem recurs reading the code is the thing to do.


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Our 3rd V70