Gas Cap Pressure Lost

[apcorgis]

I have a 2004 Outback and about 6 months ago I noticed that there was no pressure release when I opened my gas tank.  Thinking the gas cap had lost its seal, I replaced it with a Subaru parts cap, but that did not solve the problem.

 

Shortly after that the Check Engine Light came on.  After driving with the light on, it went off and stayed off for a few weeks.  I took it to the dealer and they ran a diagnostic and said the Catalytic Converter was running intermittently and that it should be replaced.  $2500.00

 

It has now been at least 6 months and the light comes on for a short time and then it goes off for a longer time. 

 

Could it be oxygen sensors?  - any suggestions.  There is no loss of power when the light comes on.  The car has about 130,000 miles on it.

 

Thanks,

Anna

[Fairtax4me]

Take the car by an auto parts store one day and ask them to scan it for codes. Most will do this for free and some are nice enough to give you a printout of the codes.

 

Post the code numbers here and we can offer more help.

 

There are a bunch of valves and solenoids that work to control vapor pressure in the fuel tank and keep the vapor contained so it doesn't leak into the atmosphere. Any one of them could be stuck open or partially open, or have a bad seal and allow the vapors to vent. The catalyst code (that the dealer quoted you $2500 to fix) is possibly related to one of these valves. More often than not that's a false code, and replacing the cats does not help.

 

There is also an issue on older models with the filler neck rusting out and getting small pinholes that let fuel vapors out. Usually this causes a gas smell in and around the car.

[Rooster2]

Take the car by an auto parts store one day and ask them to scan it for codes. Most will do this for free and some are nice enough to give you a printout of the codes.

 

Post the code numbers here and we can offer more help.

 

There are a bunch of valves and solenoids that work to control vapor pressure in the fuel tank and keep the vapor contained so it doesn't leak into the atmosphere. Any one of them could be stuck open or partially open, or have a bad seal and allow the vapors to vent. The catalyst code (that the dealer quoted you $2500 to fix) is possibly related to one of these valves. More often than not that's a false code, and replacing the cats does not help.

 

There is also an issue on older models with the filler neck rusting out and getting small pinholes that let fuel vapors out. Usually this causes a gas smell in and around the car.

+1 on Fairtax quote................for what it is worth, just a couple of days ago, my 99 OBW threw a CEL. I had the code pulled at an auto parts store to learn that the gas cap was bad. To make sure it was simply a bad gas cap, I cancelled out the code by pulling the negative cable off the battery, and waited about 10 minutes re-install. I then put the gas cap from wifes 98 OBW on the 99, and drove around for a bit to see if the CEL would reappear. It didn't, so bought a new gas cap, and now all is right. So.....if you don't have a code reader,  pull the battery cable to clear codes, and go from there.

 

I hope the dealer had less costlier ideas then just throwing on a new cat converter for 2500 big ones???