My wife's car is a 2008 Chrysler Sebring convertible.

The problem is that it won't accept more than 3/4 tank of fuel.

I took it to a local mechanic and was told it had to have a new fuel tank at a cost of $1,060. The car is 10 years old, not worth much more than the cost to replace the tank.

What could cause this?

  • how do you know its not full? Maybe the gage is off.
    – agentp
    Sep 1, 2017 at 19:54
  • Why did the mechanic say it needed to be replaced? You should ask when the cost is that much. Maybe the tank is dented, reducing the capacity. Did you ask another mechanic (second opinion)? If you don't want to spend the money, is there any reason to not drive it with only being able to fill it to 3/4?
    – CharlieRB
    Sep 1, 2017 at 20:12
  • The fuel sender (or gauge?) may be off, but that would be obvious when filling and seeing less fuel than expected. If the tank were dented, the capacity would be reduced, but would still fill to full according to the sender.
    – David Sain
    Sep 29, 2018 at 6:05
  • Very difficult to imagine how the capacity of a fuel tank could change . Apr 16, 2021 at 23:38

2 Answers 2


There is a small ball inside the fuel filler to prevent overflow. If the ball somehow falls down or is stuck, it wont allow the excess fuel.


This is most likely your EVAP system.

It could be a few things.

Some Audi A4/S4 owners complained about this specific issue and they might more prone to it, but so far I haven't experienced this. In all modern vehicles, there is a charcoal canister where the fumes in the fuel tank are stored as the tank vents when you are filling or when vapors are formed on a hot day. If it was saturated with liquid fuel (as happened with these folks), the vapor may not be able to be vented through this.

If line to the charcoal canister is plugged up, it would result in this as well.

If the canister purge valve has failed, it may not open when the engine is running to consume the excess fuel/vapor in the canister.

There may be a rollover valve on the fuel tank that is preventing the gasses from exiting the tank.

If you are in an area where the fuel pumps have a bellows to seal the filler, try to pull back slightly to allow fumes to escape out of the filler to see if this helps.

If that helps, diagnosing is the next step. You may be able to use a compressor to blow air through the evap line from the canister back to the fuel tank to clear an obstruction. With the evap line to the fuel tank disconnected, you could try to put a short piece of hose onto the canister and see if you can blow compressed air through it. If not, it's plugged and needs replacement.

If the purge valve fails, generally a DTC or fault code will be set.

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