jayboydog

Diagnostic code 0451 only. After erasing diagnostic codes, the check engine light VSC & TRAC OFF all illuminate. Situation exists for at least past six months. 14 MPG city. Was able to pass smog check by erasing codes and following a series of steps (below) to get the systems ready for smog check before code reappeared. But I want to solve the EVAP pressure system code.
gas cap looks excellent. I will rub some silicon lubricant on the rubber seal of the cap. Tell us what your experience has been with a 0451 diagnostic code.

to get the systems ready for smog check

• erase diagnostic codes (erase is a function of code reader, or disconnect battery cable for short period and reconnect battery cable)

1. start cold engine (several hours of cool down) and idle for 10 minutes.
2. increase RPM to 2000 and hold for 3 minutes
3. drive 5 miles at 55-60MPH
4. allow car to coast dropping speed to 40MPH
5. increase speed to 55MPH for a mile then stop (may use brakes)
6. idle for 1 minute
7. turn engine off for 1 minute
8. start engine and drive 5 miles at 55-60MPH and drive to smog check without turning engine off until smog check is complete.

diagnostic codes trigger Check Engine Light after two cold starts which want to avoid until smog check is complete.

Felix

I ended up replacing the evap canister.......My fault as I'm use to topping off the fuel tanks of diesel trucks, which'll take additional 4-5 gallons of fuel, like beer suds.....Once the fuel nozzle kicks off, don't add anymore fuel as my wife mentioned....Jack up the rear of the vehicle, drop the rear part of the exhaust, remove the heat sheild which is above the muffler........I used a Dorman evap canister, deleted the code & one 'n done.....

jayboydog

Did your car show any other diagnostic trouble codes in addition to P0451? Did you cease filling the gas tank past the automatic pump shut off before changing the charcoal canister? Could the issue have been a valve attached to the canister? Could your old canister get back to functioning if given time after ceasing to overfill the gas tank?

Felix

Yea for the code....I deleted the code & it came back on after a bit, so I bought the canister & was going to swap it out on the coming up wkend, then the mil went off, great returned the canister. Came back on, of which, I couldn't get it to stay off for a couple weeks, so I rebought the canister & installed it, deleted the mil & no problems since then. btw it was getting pretty mileage.....

bcolins

do you happen to have the part number for that canister?

bcolins

In Texas a state auto inspector told me that cars would still pass inspection with one "Not ReadY" and further added that evap circuits were generally the last post reset test to complete,.......so suggesting that I do a reset all codes, then while watching my real time inspection data on my scanner, drive until all were ready EXCEPT EVAP,...then go and get the car inspected. Easy Peasy.

4oohUrsula

Here's my story:
Had the 0451 code that kept coming back
Tried new gas cap, no luck
Tried new FACTORY gas cap, no luck
Took to smog shop for smoke test, they could not find the problem but they suspected the vapor canister.
I replaced the vapor canister with one from RockAuto, no luck.
I bought 2 other purge valves and planned on installing them.
When i removed the air box to replace the upper purge valve I found that the 2 electrical wires going to that valve were BROKEN. woohoo! I've never been so happy to find broken wires! I think vibration from the airbox just eventually wore through them. I fixed the 2 wires, put it back together, deleted the code, and it never came back.
So what should have been a 1/2 hour (and basically free) fix ended up costing me hundreds.
Only thing i can advise.... spend more time on diagnosis and less on parts. Try to put eyes on everything and check for obvious problems (cracked hoses, broken wires, damaged parts, etc.)
THE END.
Hope this helps someone...

Felix

Dorman #911-653.....