Just wanted to post my findings to give others some ideas to look at as these cars are getting older


2001 Max GLE with 125k miles on it. Had the dreaded evap codes come on so I started with the easiest cleaned the gas filler neck as it was a bit crusty cleared codes and they came back. Next I replaced the canister and the purge valve as the canister was throwing charcoal as well, Cleared lines and installed new used valve and canister valve was tested to be good and canister was solid no issues, still had codes.


At this point I gave up and drove the car for a few more months and developed an exhaust leak as well so I gave up completely and bought another car. Move forward a year and I gave the car to my brother as he needed something to drive.


Since the car was going to be transferred to him it had to be fixed right so he has a buddy who is a mechanic running his own shop so the car went there. Exhaust turned out to be the top of one of the cats blew out as well as the flex connector, replaced cats canister and purge valve or vent valve, same codes and a few more. Oxygen sensor codes and P0325 knock sensor, P0455 and the other one I cannot remember at this time. I felt the knock was a ghost code and the oxygen as well from driving with the cat open like that so we dove into the evap codes once again. tested everything for leaks found none but then we got a code for the CUT VALVE yeah something new to look at. Removed the cut valve assembly from the car and bench tested it and it would not move. Went to wrecker and remove the complete assembly from another car tested it and found it operational. Installed on car, cleared all codes and drove for two days with no lights, WE WON!!!!!!


This kind of thing can be a pain in the butt as it was throwing all sorts of ghost codes but if you start with the basics and work it through you will find the culprit.


Now for the new lights that popped up, all the brake malfunction lights came on yesterday so we need to start looking into that. The car has been sitting for 6 or 7 months since it was driven so there are going to be some quirks. Car is scaley with rust as it was abused before I even got it and when I did I had to replace the rad cradle and the rear calipers so I am hoping when we pull the codes it is just a bad sensor on one of the wheels or maybe even something simple like a connector at the left rear wheel as we were working in that area so much.

 

why is P0455 dreaded? i just had my codes scanned and
P0455 is one of them.what is a CUT VALVE assembly?

 

If you do a search on the P0455 and the other evap codes that come up you will see it can be dreaded as it takes time to diagnose. If you do not have the proper equipment to diagnose you will end up throwing parts at it to figure it out, that is what I have seen from previous threads.


I did a great deal of reading and checking things to try and find the issue. All info I put together on this I got from this forum by searching.


The cut valve assembly you will have to search for what it is and what it looks like as I did it that way. I cannot remember what it does I just went by the picture I found here and replaced it since it was not working.

 

p0455 is large evap leak. Rather than throwing parts at it take it to a shop that can run a smoke test on it to find the leak then replace whats needed.