Hey guys Ive had my stang (2001 gt) for a while now and this forum has provided me with so much info and help. (special thanks to cliffyk) So much so that Ive decided to contribute by sharing my experience with those who are dealing with the dreaded p0455 and p0457 codes. Some of this information may seem a bit stale but the purpose is to hopefully help those who were stuck like I was, and maybe when others look to resolve their problems they may stumble upon this thread.
So we know that both codes are related to the evap system, specifiically:
P0455-EVAP Control System Leak Detected (No Purge Flow or Large Leak)
P0457-EVAP Control System Leak Detected (Fuel Filler Cap Loose/Off)
for any other trouble codes refer to (again thanks cliffyk)
PaladinMicro
Now the first thing people will tell you, especially if both your CEL and check fuel cap lights are on like mine were, is to check your fuel cap. I ended up going up to my Fire Stone Complete Auto Care and had them pressure test my cap. It was still a good sealing cap.
I went to the next common probable cause...the fuel tank grommet and or the filler neck. My neck was a bit rusty but didn't pit through, mainly just dirt and surface rust. The actual grommet however was pretty bad and was in need of replacement. I changed it but that didn't resolve any problems.
So now you can imagine my frustration after doing what most people have suggested lol. I ended up going back to firestone and had them run a engine diagnosis, WHICH IS NOT THE SAME as a free autozone obd scan i can assure you. The 80 bucks spent for that diagnosis went toward a complete smoke test and various pressure/vacuum tests until they finally determined the problem. Mine happened to be the VMV (vapor managment valve) which come to find out is the same as the purge valve. they told me it was stuck closed.
So now i was at the point where I had to decide how much money i was willing to spend, i had a two options
*I could just leave the car with them and have them repair it, $286 for parts,labor, and diagnosis fee.
*i could just pay the diagnosis fee and replace the part my self, around 124 ( the part on rock auto is 43, they were charging 88)
Technically, I could have even not went to Firestone and deal with the headache of replacing random Evap parts also lol
I wasn't really feeling paying close to 300 if it was just the purge valve. Seriously, the part was only 43 and I knew I could change it myself. But then I remembered how much of a pain in the rear some folks here said the Evap system can be. Firestone even said that they would resmoke the system after they replace the part to double check for leaks and if the codes come back, to take it back and it would be free of charge.
After I did some thinking, I decided to bite the bullet and complete the job with them. I even got my car back in less than 24 hours which was pretty cool. They even did a courtesy check to inform me of suggested maintenance. (tires,plugs,wires, etc.)
I was a bit disappointed when i didn't get 15 dollars off the Diagnosis fee like the gentleman I spoke to over the phone said i would. It was an offer he gave me after I had asked if they'd waive the diagnosis fee since i was having my repair done there but they couldn't. It wasn't till i got home when I noticed I was charged full price :/ lol
all and all I'm glad with my decision and didn't mind paying the extra money for that sense of security. Ive driven bout 200 miles and no problems since then. This little thread may go unnoticed but hey like I said before I really appreciate community that was willing to help me out so Ill return the favor. PLUS I'm so tired of finding threads with problems that never state whether they got their problem resolved or not. If anyone has any questions I'm more than willing to help out if i can, there are no stupid questions.
Thanks again everyone!
So we know that both codes are related to the evap system, specifiically:
P0455-EVAP Control System Leak Detected (No Purge Flow or Large Leak)
P0457-EVAP Control System Leak Detected (Fuel Filler Cap Loose/Off)
for any other trouble codes refer to (again thanks cliffyk)
PaladinMicro
Now the first thing people will tell you, especially if both your CEL and check fuel cap lights are on like mine were, is to check your fuel cap. I ended up going up to my Fire Stone Complete Auto Care and had them pressure test my cap. It was still a good sealing cap.
I went to the next common probable cause...the fuel tank grommet and or the filler neck. My neck was a bit rusty but didn't pit through, mainly just dirt and surface rust. The actual grommet however was pretty bad and was in need of replacement. I changed it but that didn't resolve any problems.
So now you can imagine my frustration after doing what most people have suggested lol. I ended up going back to firestone and had them run a engine diagnosis, WHICH IS NOT THE SAME as a free autozone obd scan i can assure you. The 80 bucks spent for that diagnosis went toward a complete smoke test and various pressure/vacuum tests until they finally determined the problem. Mine happened to be the VMV (vapor managment valve) which come to find out is the same as the purge valve. they told me it was stuck closed.
So now i was at the point where I had to decide how much money i was willing to spend, i had a two options
*I could just leave the car with them and have them repair it, $286 for parts,labor, and diagnosis fee.
*i could just pay the diagnosis fee and replace the part my self, around 124 ( the part on rock auto is 43, they were charging 88)
Technically, I could have even not went to Firestone and deal with the headache of replacing random Evap parts also lol
I wasn't really feeling paying close to 300 if it was just the purge valve. Seriously, the part was only 43 and I knew I could change it myself. But then I remembered how much of a pain in the rear some folks here said the Evap system can be. Firestone even said that they would resmoke the system after they replace the part to double check for leaks and if the codes come back, to take it back and it would be free of charge.
After I did some thinking, I decided to bite the bullet and complete the job with them. I even got my car back in less than 24 hours which was pretty cool. They even did a courtesy check to inform me of suggested maintenance. (tires,plugs,wires, etc.)
I was a bit disappointed when i didn't get 15 dollars off the Diagnosis fee like the gentleman I spoke to over the phone said i would. It was an offer he gave me after I had asked if they'd waive the diagnosis fee since i was having my repair done there but they couldn't. It wasn't till i got home when I noticed I was charged full price :/ lol
all and all I'm glad with my decision and didn't mind paying the extra money for that sense of security. Ive driven bout 200 miles and no problems since then. This little thread may go unnoticed but hey like I said before I really appreciate community that was willing to help me out so Ill return the favor. PLUS I'm so tired of finding threads with problems that never state whether they got their problem resolved or not. If anyone has any questions I'm more than willing to help out if i can, there are no stupid questions.
Thanks again everyone!