Vacuum seal

My check engine lite stays on. I was told it MIGHT be the vacuum seal on the gas tank. How much should I expect to pay to get this fixed? and how long should this repair take?

Could be a bad gas cap. You need to take it to Advance or Auto Zone and get the code read for free. Come back and tell us the codes.

Sorry, I left that info out and I have -3- gas caps. Codes are: P0551 - pressure circuit; P0442 - EVAP; P0455 - Purge Valve Short; P0456 - same as P0442. Like I asked; how much should I expect 2 pay for vacuum seal & how long should it take to fix. I do NOT mean to sound ungrateful; I spent over $500 with 2 mechanics that have licensed garages and the lite is still on. How do you think I got -3- gas caps. (smile)

The PO551 code indicates a loss of pressure in the power steering system, which is a problem but not THE problem. Check the power steering fluid level, and add the correct fluid if it is low. Check for a leak as well, under the car on the ground where you park and under the power steering unit itself. Power steering fluid is under high pressure and will run out very quickly if there is a leak. If it is leaking, get it repaired ASAP. The PS is not cheap and the fluid is just one more thing running off the roads into storm drains.

So likely the problem has to do with the code PO456. I would have replaced the gas cap first as well, since it is the cheapest and easiest solution and it makes sense.
But this code doesn’t reference gas caps. Read the link http://www.obd-codes.com/p0456.

Could also be a bad purge valve or a bad connection in the purge valve circuit.

Provide a detailed list of everything that those 2 mechanics have actually done to address the evaporation system issue (the P04xx) codes. Has anyone, for example, used a smoke test on the evap system?

And P0455 is a gross (large) leak. Not a purge valve short. So all of your evap codes are about leaks.

Most of the time with Chryslers, the evap problem is a rotten, split hose.