I have a 2001 bonneville that has 144,000 miles. Two weeks ago my car start sputtering and the check engine light was flashing. So 1 code I keep seeing is 0440. I have turned up the car. New plugs
New plugs and wires. Air filter, new egr
valve, fuel filter and where the spark plugs
go guess the module brand new replaced.
The sputtering stop but the check engine
light won't go away. What else can I do to
fix this issue? I need to pass emissions by
end of this month.
That is an evap code. Could be bad /loose gas cap, bad purge solenoid or canister, or a leak somewhere in the evap system. Topping off the gas tank can cause this, gas gets into the vent of the evap system. The most common problem is a gas cap though.
Trouble code P0440 is for the EVAP system. The EVAP system routes gasoline fumes back to the engine to be burned instead of releasing them into the air. The computer has detected a leak in the system. That's why the check engine light is on and the trouble code is in the computer. The very first thing to do is check or replace the gas cap. Make sure it's on securely. If it's not, you'll have this problem. If the gas cap is ok you'll need to have a smoke test done at a service facility. Because your car is a post-1999 model the leak may be too small to be seen with the naked eye. The shop will force a harmless smoke in the gas tank and carefully inspect the EVAP system hoses to see where the smoke is coming out. Where they see smoke is where the system is leaking. Once the leak is fixed be sure they clear the computer. Then drive normally for about 1 week to set the readiness monitors for your emissions test. During this time keep your gas tank between 1/4 and 3/4 full. No more and no less. This way all the tests will run, all the readiness monitors will set, and you'll be good to go to inspection. HTH. -Jim
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