GS4hunnit

Its a 1999 GS400

GS4hunnit

Whats weird is, since ive replaced the VSV the CEL seems like it comes off and on as it pleases. Could something be loose? Yesterday, the CEL turned off, turned on, then turned off all withing 175 miles. Weird.

CurlyG

I bought my car in 2020, and it came it several CEL codes, including P0440, indicating an evap leak that could be located anywhere from the front to the rear of the car. After weeks of troubleshooting, I smoke tested the gas tank, and found smoke leaking out from on top of the gas tank. To see this, I had the rear seat bottom removed (easy to do, lift hard along the front edge).
The gas overfill valve on top of the gas tank had cracked, and was leaking. I had to drop the gas tank to find it (which meant dropping the exhaust and heat shields, doable, but not fun). Oh, and the gas fill hose (from the fender gas door to the gas tank) was rock hard, and had to be cut to drop the tank. I replaced the valve and gasket with:

• 77390-30071 over fill vent
• 77179-33010 gasket

And while I had the tank dropped, I also replaced:

• 77404-30011 other vent hose on top of the tank

I replaced the gas fill hose with a 1" ID hose from "Filler Neck Supply", but it disintegrated after 1 year. I ultimately replaced it with a very robust hose from McMaster Carr, P/N 5282K65, $10 plus another $8 for shipping, 1 foot is enough (had to cut off a few inches). It's like the gas fill hoses at gas stations. It's not pre-molded in a 90 degree bend, so it's a mother to install, as the two steel coils molded into the rubber wall don't want to bend 90 degrees. With enough effort, the hose will bend into place. This fill hose fits perfect, and looks awesome!