Plan B

Several years ago I began getting a check engine light on my Subaru Outback. The code was being caused because the emissions self check determined there were unturned hydrocarbons, venting directly from the gas tank to the atmosphere, not through the char-coal canister as designed. This is often referred to as “the gas cap code”.

The light came on more frequently until several months ago when it remained lit all the time. A couple of weeks ago I pulled in to a gas station. The pump island was not level. The driver’s side of the car was several inches lower than the right side. As I topped off the tank I smelled gas, and saw gas dripping down from the tank. Ugh!

I put the car on the lift and found gas seeping from a plastic valve on the top of the tank. Now, Subaru was kind enough to put an access panel in the floor, under the rear seat, to access the fuel pump. They were also kind enough to place an access cover over the fuel sending unit. Servicing these two items is quite easy, and does not require dropping the tank. Unfortunately, there is no way to access this plastic valve without dropping the tank. The two access covers are very far from this plastic valve.

To remove the gas tank on this car, first the drive shaft, rear axle, rear suspension and the exhaust system needs to be removed. Then, the tank can be lowered. When pricing parts, I discovered the gas tank straps are no longer available from Subaru, and not yet available in the aftermarket.

I had a hard time justifying the time and expense to perform this task on a 14 year old car with 247,000 miles on it. If there was only a way to ac-cess the valve from inside the car, if only…

subaru gas tank removalWell, it took less than a minute to cut a hole in the floor with my saws-all. After the valve was replaced it took about ten minutes to weld the metal back the way it was. Interestingly, it looks like the valve failed because something dissolved the plastic, I believe it was ethanol. This was also a good time to coat the area with a liberal thick coat of Fluid Film.

With the valve replaced the threat of gas vapors was gravely reduced it was safe to weld. I was more than a little on edge welding so close to the gas tank. I placed a piece of sheet metal between the tank and the floor. I had two fire extinguishers and water on hand, just in case.

Yea, this was a hack job, but a very well done hack job.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

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