2001 p0455 ca smog fail

Discussion in 'SN95 4.6L Mustang Tech' started by 01blackvertgt, Sep 27, 2008.

  1. :( Hello, I am a new member, I live in CA and have the following issue with my convertible 2001 gt stang. I had the low coolant level light come on and after filling up the fluid I erased a pending P0455 code. since trhis is the only way to erase the low coolant level.
    the next morning I took the stang to get smogged, it passed both low and hig dyno tail pipe tests, but failed because the computer was NOT running any of the 5 diagnostic systems.

    The tech told me to put 50 miles and then bring it back to re-test it.

    I am triyi8ng to be proactive and since I had a P0455 last year that just went away by itself till now, after replacing the gas cap, I also had overfilled it. I have traced all the hoses anf lines from engine to fender valve to gastank to left rear cannister. also the rubber seal between filler and tank.

    I replaced the vacum hose that goes from the intake manifold to teh fender valve. and seinvce I had bought a 10 dollar AutoZONE gas cap, I went to my local dealer and spent the 35 dlls for a ford gas cap. I am going to drive the 50 miles or more before I take it back to the smog shop.

    I was wondering is any one knows what else I could check, and has anyone ever experienced issues overfilling tha gas tank.

    Thanks a bunch. I will post after 50 miles to let you know what happens.
  2. just drive it. when you clear the codes the car has to run all monitor readiness checks to pass smog. theres nothing wrong, just drive it.

    I drove him today for 94 miles and I checked it afterwards with my code reader, no codes where present, not even pending. but my "cat" and "evap" monitors still show "not ready"

    Any Idea how many more miles before they come on? or do I take it to the smog shop for re-test as is?

    Thanks for your response.:(
  4. 01blackvertgt:

    Run a "google" on "Ford drive cycle" or Ford+"drive cycle" and you will be rewarded with a step-by-step procedure for getting every monitored system run through and ready for the OBDII test.

    The evap test usually takes a few cycles of cold engine to hot engine with some driving in between. Not sure why the cats are not ready. I went through the same thing because Missouri has a very 'deep' probe of the emissions systems, not just checking for codes anymore. Check if you can apply for an emissions waiver, too. In MO, if you drive less than 12,000 miles in 2 years, you can get a waiver. Maybe the same thing applies in CA?



    :D took black beuty to the smog this morning and it PASSED.

    I will wait and see if the code comes back, I will be carefull NOT to top off. I found the charcoal cannister behind the rear driver side tire. and checked all connections for the evap system. but since I replaced teh hose from the Intake to the first valve and got a a new gas cap from ford, I do not know what fixed it.

    Any way, I am now a member of this forum and plan to be pro-active.

    Thank you gentlement for your input. :nice:
  6. Check the vapor purge valve located in the passenger front fender well. $32 on rockauto dot com.
  7. 01blackvertgt:

    Thanks for posting an update. Congrats on passing (I'll bet you're breathing easier now, lol).

    Welcome to the board, too.

  8. still no MIL

    You are right CHris, my stress levels are lower, plus my B-day is Monday. Throwing a "carne Asada" on saturday.:lol:

    I still need to shock the "test only" smog place with My 76 Ramcharger with 440CID and only a EGR valve, the good old days. this beast is smog legal with 488 ft lbs of torque.:nice:

    As for the STANG, I have run thru 350 miles and NO MIL. I will keep you posted. As for the valve in the inner passenger fender, I did check it and it is "normally closed" as should be. I will trouble shoot if the code returns, knock on wood. I am hopig that the vacum hose and new ford gas cap took care of it.

    Thanks for all the work, I now understand why my little bro bought a 1974 and 1976 broncos. 302 and 351 and NO SMOG required.:nono:

    George :rlaugh:
  9. P0455 BACK

    :( it has been 2 years since I smoged black beauty and the p0455 is back, passed the visual, the dyno-tail sniffer test, but not the computer to computer hand shake, was told to drive the car again.
    since I had been smelling gas every time I fill up, for the last 2 months, I changed the filler to gas tank grommet (rubber donut), since I changed Jobs I only drive 20 miles each way and the diagnostics take a long time to be ready, with the cat being the slowest, I keep throwing a P0455 code.

    I took it to a mechanic and he told me to replace the EGR solenoid, cause the stang was revving a little high, I did and the revving stopped (not a total waste of money) but the P0455 code is back.

    It is really hard to leave the stang at a shop because it is my only mode of transportation, i got rid of the 76 ramcharger and am in the middle of rebuilding a 75 Bronco, smog exempt.

    What should I try next, I plan to chase all hoses and check for vacuum leaks with carb cleaner. what do you guys suggest?? I have heard of smoke machines, but they are expensive (900 dlls) any suggestions are appreciated.

    BTW, I am now all FORD, 01 stag, 05 navigator and the 75 EB.
  10. P0455 - EVAP Control System Leak Detected

    Use your nose. Do you still smell gas? Where is the smell located? This will also help narrow down where to look.

    Double check the gas tank filler neck. Look for rust esp under the plastic guard. Next inspect the grommet between the gas tank and the filler neck. Remember that gas vapor are hard on rubber parts. Leaks are the usual result and the two locations mentioned should be consider #1 and #2 for an older Mustang.

    Next, check the vapor lines to the filler neck. There are two.

    The vapor lines run the length of the car. The hard lines are not likely to leak. But the rubber ones are. Follow all of the vapor lines from the TB back to the right hand firewall.

    Other possible leak locations are more difficult to trace. IMO, the easy ones should be ruled in/out first.

    P0455 - EVAP Control System Leak Detected (No Purge Flow or Large Leak)

    • After-market EVAP hardware (such as fuel filler cap) non-conforming to required specifications
    • Disconnected or cracked fuel EVAP canister tube, EVAP canister purge outlet tube or EVAP return tube
    • EVAP canister purge valve stuck closed
    • Damaged EVAP canister
    • Damaged or missing fuel filler cap
    • Insufficient fuel filler cap installation
    • Loose fuel vapor hose/tube connections to EVAP system components
    • Blockages or restrictions in fuel vapor hoses/tubes (items also listed under disconnections or cracks)
    • Fuel vapor control valve tube assembly or fuel vapor vent valve assembly blocked
    • Canister vent (CV) solenoid stuck open
    • Mechanically inoperative fuel tank pressure (FTP) sensor
  11. will do

    :nice: I already replaced the filler to tank grommet, I will smell for leaks and trace all lines Saturday, i am also going to replace the Vapor canister purge valve, I checked it 2 years ago and it was NC. since I need to jack, remove tire and inner fender, I will replace this time.

    I will also check the filler for leaks, when you say "under plastic cover", do you mean inside the trunk? it is a convertible.

    I was told to put 20 lbs of air in thru the gas filler opening (using some kind of plug) and to listen for air escaping (engine off), any one done this??

    I remember all of this starting when I over filled the car (fuel). Any one else having had this issue after over filling??
  12. On many Mustangs the filler neck has a plastic rock shield zipped tied around the metal filler neck. The plastic will trap water and over time will cause the metal filler neck to rust out.

    Please don't take the advice of someone who told you to pressurize the EVAP system to 20 PSI. Such a pressure is 40 times higher than designed and would almost certaintly break something.


    The EVAP system can be pressurized to 3.48 kPa (14 inches H 2 O). Which is 0.504 PSI! Hardly enough to make much of a sound. This is why a Professional would use a smoke machine.

    The clue about overfilling is important. This greatly increases the possibility that raw gas has been drawn into the charcoal canister. Raw gas will turn the charcoal into jelly thus ruining it.

    Consider replacing it. It is only a $80 part. This would also offer a great chance to inspect the vapor lines to/from the charcoal canister.
  13. The lord works in misterious ways

    I was supposed to do the 20 lbs pressure test this past Saturday, but my air compressor died and the one I was borrowing did not get here in time. I will change the canister tonight and the purge valve, assuming that O'rilleys has them in stock.

    I spent a couple of weeks in the Imperial valley (southern California) 115 degrees of desert dry heat, those 2 weeks plus the 3 months later I did not get the P0455 code (or any evap codes, or other codes). do you think the gel might have dried on the heat?

    I let you know if I get to replace them tonight. Thanks for the help.

  14. ouch

    :rolleyes:well, it hurt a little but black beauty deserves the best $150 vapor canister from my local Ford dealership, amazingly easy to replace, the old canister weighed at least twice of what the new one does. sounds like I must have had fuel in it.

    I will drive it and if i get the error code again I will replace the purge valve. I did check the vacuum hoses in the engine compartment, no leaks found.

    I will report back later, wish me luck.:lol:
  15. Never over fill your car and NEVER take your car to a smog test with a full tank of gas. Go when it's around 1/2 tank. You won't get as much vapor.
  16. I hear you, I hope this is it:nonono: $150 dollars is a hard pill to swallow.

  17. got the p0455 this morning, 60 miles after replacing the vapor canister, will replace the vapor canister purge valve and check all hoses and connections tomorrow morning. I might take a 100 mile drive this weekend to check the results.

    any one know after how many miles the cat does it's diagnostics?
  18. The CV vent solenoid is easy to test. Remove it from the charcoal canister. You should be able to blow through it easily when no power applied. Apply 12 volts from a battery charger and then you should not be able to blow through it. If it passes this functional test, likely the CV vent solenoid OK and is NOT your problem.

    The purge valve is also easy to check. Except you should not be able to blow through it with no power. Once power is applied, you should be able to blow through it.

    IMO, you sould look first for leak sources. Esp since the DTC calls out a large leak. If this is a solenoid, more likely to be the purge solenoid stuck closed. Replacing parts without testing first is likely to just make your wallet lighter and improve the autoparts store's bottom line.

    Confirm if the gas cap has been replaced. This is a 2001 and the gas cap is almost 10 years old. I recently had to replace mine because of a slow leak DTC. OBTW, the old gas cap looked perfect.

    Confirm that the filler neck is rust free. Double check the gas tank grommet.

    Confirm the vapor lines from the intake manifold to the right hand fender well are in good shape and leak free. Remember that gas vapors are hard on rubber parts.

    Confirm if you are still smelling gas and where it it coming from.

    100 miles for cat tests to complete is somewhat excessive. The "fail" threshold is set fairly high. An extended period for all readiness tests to complete sometimes indicates a problem.

    Also consider that some DTC's will disable other tests. It is possible that a failed EVAP system will stop other system tests from finishing.
  19. thanks, will check before buying. the gas cap was replaced 2 years ago from ford and the filler grommet 2 weeks ago. I will remove the filler neck for rust.

    Thanks WMBurns,
  20. BTW, no more gas smell