I just purchased a 1999 V70 XC. It has 70.5K miles on it.

I haven't even gotten the title, yet, and the check engine light came on. My OBD II scanner says that the code is P0455, Evaporative Emission Control Leak Detected (gross leak). I cleared the code and light and it came on again within a day.

Everyone I have talked to suggested that this is simply a case of a loose gas cap. I took the gas cap off and screwed it back on again as tightly as I could, but the light came back on again.

Is this necessarily the gas cap? Do these cars have problems with gas cap leaks? There is a service bulletin out there on checking for gas cap leaks.

Thanks in advance for any help.

 

You can start under the hood. Look by the cooling fan there is a Valve mounted in the fan with an electrical plug and 2 hoses on it. One comes from the intake and the other goes back to the Gas tank.
A leak in the line will throw the same code.

 

Thanks. I will check that out.

 

I looked at the hoses, but didn't see any leaks. However, as my gas tank emptied the check engine light went out on its own. I have filled up three times since without the light going back on.

 

Watch and see if it comes back on. The code is most likely still stored in the computer though.

 

I have a 1999 Volvo C70 Conv with the identical problem......

I was getting a code with the ABS sensor, check engine, and trac control lights all at once and managed to fix that by having the ABS module rebuilt ($79).

After I got that repaired I started getting this P0455 code. It will come on and go off by itself every week or so. It comes on for a week and goes off for a week.

I wonder if it may actually be a faulty gas cap. It seems like it is related to the gas cap, but there is no way to tighten the cap anymore since it just keeps clicking. I may go out and buy a new cap (depending on the price from the dealer).

I will keep you posted on how I make out. Let me know if you are able to track down the issue if you find anything.

Thanks,
David

 

So you were going to keep us posted.... did a new cap fix it? What kind of cap did you get? Any recommendations from anyone on a brand? Is Standt good enough or should I go straight to the dealer?

 

I had this problem befor.
You need to Replace your purge valve filter ,and if the charcoal leaks ;In addition, you should replace the fuel filter as well.
wait a day for this to clear.
you cloged the fuel lines maby.
"Don't overfill the gas tank afterone click from the gas pump."
If this wont work then you have a feul leak,
or gascap O ring needs to be replaced.