I have a 2007 sonata with a v6 engine with 287000 miles on it and I've noticed a code came up P0455 . I tried replacing gas cap and code still there . I dont know what is wrong.
You have a leak in your evap system. That's a 15-year-old high-mileage car, although a bad gas cap is listed as the most frequent cause of this code there are others:
https://www.fixdapp.com/blog/p0455-code/
Is it something to worry about or a safety issue? Car drives the same. Just noticed gas mileage is less
As long as there are no gas fumes or visible leaks it's not a safety issue. Of course if you're in an area that tests for emissions it's not going to pass like that. Since it may get worse I'd recommend getting it fixed.
When I opened the gas cap cover I smelt a wif of gas and when I open the gas cap its wet/damp.
Could be the fuel filler hose has deteriorated. Best to have the problem checked out rather than gamble with gas fumes. Take it to a good independent mechanic, not a chain shop like Pep Boys or Firestone, and certainly not a stealership.
Do you know why where the gas cap seals and inside that area is always wet? I checked under the car and everything seems dry
Might be a side effect of the evap system problem.
Could it be component problem ? Cause as car is running I dont see any leaks dripping of anything . Also, how could I find an independent mechanic?
Can't really tell from a distance what's going on, could be almost anything in the evap system. A mechanic would likely use a smoke machine to find any leaks.
Best way to find a good independent mechanic is through recommendations of friends, family, and co-workers.
I bought a new gas cap and code was still there so I paid for smoke test. They said canister vent valve was faulty and leaking. So I've replaced that and code came back 2 days later. I would think its maybe a line but they said they didn't see any bad hoses and it was only leaking from the vent valve. I paid $65 for smoke test and 60 for the part.
So on a website of the diagram the only thing that I could possibly try is replacing purge valve. How can I test it without smoke machine or scan tool?