On my 97 E420 w/87k I am getting an error code of 0455 at various times and the low fuel light starts to flash when stopped for longer red light at idle. I understand from what I have read that this is most likely a leak in my closed fuel system. I have purchased and replaced the fuel cap but did not solve the problem. Are there other components that could be bad? If not, my plan is to make a gas cap, us a regulator and air supply to put 3 to 5 lbs of preasure in the system and soap the lines to check for leaks. Any other suggestions would be appreciated.

GW