My gas tank is not venting properly. It either has a vacuum or is over pressurized. The fuel pump has been replace 4 times in the last 500 miles.
Aug 31, 2025 at 10:21 PM
Gas tank pressure?
1985 MERCEDES BENZ 380SL
MERCEDES 380SL
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The number one reason for the tank to have pressure is a vent valve failure, here is a diagram of the system so you can see how it works and the vent valve location. I would replace it which should fix the problem. Check out the images (below). Let us know how it goes.
Image (Click to enlarge)
Sep 2, 2025 at 8:21 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.