Anyone know what the trouble code P0456 means? All the sites I have visited don't have that one. Any help would be greatly appreciated.

 

Found it. It is a small leak in the EVAC system somewhere. Probably one of the hoses. FYI

 

do you know if that effect the ac. i just re filled my car with 2tanks of freon and literally 3 hrs later its back to blowing hot air.

help please.

tony

 

No, P0456 is for a small leak somewhere in the fuel system, usually it is caused by a bad gas cap.

You should take it to a shop and have them run some dye through it and find your leak with a blacklight.

 

I would not recommend using any dyes as those are just contaminants for a A/C system. Just take it to a A/C shop and they usually have a freon sniffer than can find the leak. If you threw two bottles of freon at it and it is gone in a few hours, you definitely have a big leak. You should at least have heard the leak by running the A/C for a few minutes after filling it up and then turn off the engine and then find the leak. The most obvious and common place to find your leak, especially a big leak would be the condensor coil that is mounted in front of the radiator. You can get a spray bottle and mix up some dish washing detergent and water and spray on the condensor to find the leak. If no leak is found the spray on the all the fittings and spray around the compressor. If there is no leak you can find under the hood, the leak may be the evap coil. You would definitely be smelling freon inside the D if it were a big leak also.

 

I had the same code for a while, took a few tries but finally got it cleared. Here is what areas I checked, so that should give you a starting point.

Under the frame, drivers side, forward of the fuel tank.There are two lines attached to the EVAP CANISTER I had dryrot on one of them, but since I was in the area I replaced both of them. Heads up, it is a flared fitting, and one end is larger than the other.I was able to use AutoZone scrap hoses so that was a bit cheaper.

Fuel Cap, take the dealer route, mine was only about $10

Emission hoses, there is a hose, followed by a hard plastic line then another hose. It comes off the PCV Valve(HOSE) then hard plastic line, then
the other end is a hose fitting that connects to the intake manifold between the manifold and firewall. There is no easy way to explain but you should be able to feel for the hose and replace it.

Obviously check other vapor hoses in the process, for leaks, tears etc...

The M.I.L came back another couple of times, but it went out finally and has been cleared for about two months now.

Good Luck!!!