Problem with my 2000 PONTIAC GRAND AM GT
3400 V6
dash lights = CHECK ENGINE LIGHT
codes = P0449
tech = JK
question = Why does my car HAVE A CHECK ENGINE LIGHT on. IT IS FOR P0449. I
CHECKED THE VENT SOLENOID AND IT IS TURNING ON AND OFF. COULD THE
SOLENOID STILL BE BAD? WHAT ELSE SHOULD I DO? THANK YOU
JK:
If the vent valve is functioning, it is POSSIBLE that the solenoid in the valve is functioning,
but the resistance is either too high or too low, and the PCM sees that and sets the code.
If you do not have any leak codes along with it, then i would say to check the resistance of
the wires between the pcm and the solenoid. No more than .2 ohm on each. Make sure
not grounded, and not shorted together. If the wiring all checks out, then i would replace
the solenoid and clear codes. Also, be sure you are checking the vent valve, and not the
Purge valve. Purge valve is on the engine, vent is under the rear of the car.
3400 V6
dash lights = CHECK ENGINE LIGHT
codes = P0449
tech = JK
question = Why does my car HAVE A CHECK ENGINE LIGHT on. IT IS FOR P0449. I
CHECKED THE VENT SOLENOID AND IT IS TURNING ON AND OFF. COULD THE
SOLENOID STILL BE BAD? WHAT ELSE SHOULD I DO? THANK YOU
JK:
If the vent valve is functioning, it is POSSIBLE that the solenoid in the valve is functioning,
but the resistance is either too high or too low, and the PCM sees that and sets the code.
If you do not have any leak codes along with it, then i would say to check the resistance of
the wires between the pcm and the solenoid. No more than .2 ohm on each. Make sure
not grounded, and not shorted together. If the wiring all checks out, then i would replace
the solenoid and clear codes. Also, be sure you are checking the vent valve, and not the
Purge valve. Purge valve is on the engine, vent is under the rear of the car.
Other related articles:
Other related questions
WARNING LIGHTS
Check Engine / Service Engine Soon / SES light
Todays GM vehicles use many sensor, switches, solenoids, and other electrical components to control or monitor
every aspect of the engine.
From controlling the fuel and ignition systems, to monitoring the emissions.
A problem in any of these systems, or subsystems, can cause the check engine light to come on.
The first step in any diagnosis of the check engine light is to get the computer (PCM or ECM) scanned for codes.
Any time this warning comes on, a code is stored in the computer memory along with many data parameters that
were present at the time of the fault.
Todays GM vehicles use many sensor, switches, solenoids, and other electrical components to control or monitor
every aspect of the engine.
From controlling the fuel and ignition systems, to monitoring the emissions.
A problem in any of these systems, or subsystems, can cause the check engine light to come on.
The first step in any diagnosis of the check engine light is to get the computer (PCM or ECM) scanned for codes.
Any time this warning comes on, a code is stored in the computer memory along with many data parameters that
were present at the time of the fault.
Question:
2002 Chevy Silverado 2500HD.
Warning lights = Service Engine Soon.
Codes: EVAP input low
Replaced purge solenoid assembly. Question: Low input to evap could the canister be bad or ?
2002 Chevy Silverado 2500HD.
Warning lights = Service Engine Soon.
Codes: EVAP input low
Replaced purge solenoid assembly. Question: Low input to evap could the canister be bad or ?
Answer:
There are many components to the EVAP system on your Silverado. A low input code refers to voltage
levels at a sensor. The canister itself has no electronic sensors so it most likely is not bad. A general check
of components should be done to check for system leaks to start. A good sealing gas cap, preferrably
factory, is necessary as well. If you've changed the Purge Soleniod up near the top of the intake manifold,
you should check the Vent Valve underneath the truck located at the rear of the gas tank. There is an
updated design from GM for your vehicle. Wiring and connectors should be checked for corrosion and
wear. There is possibly an updated PCM software calibration that needs to be done as well.
There are many components to the EVAP system on your Silverado. A low input code refers to voltage
levels at a sensor. The canister itself has no electronic sensors so it most likely is not bad. A general check
of components should be done to check for system leaks to start. A good sealing gas cap, preferrably
factory, is necessary as well. If you've changed the Purge Soleniod up near the top of the intake manifold,
you should check the Vent Valve underneath the truck located at the rear of the gas tank. There is an
updated design from GM for your vehicle. Wiring and connectors should be checked for corrosion and
wear. There is possibly an updated PCM software calibration that needs to be done as well.
| 12-3-10 are there software calibrations needed on any other makes or models specifically my 2004 grand am with a 3.4 v6 what do you mean by updated design? for the vent valve or the evap system over all or ?? |
Comments
| There are no updated software for this problem, but there may be for others. The only way to tell is to have the car hooked up to dealer terminal and compare software versions with what is in your cars modules, and what / if any updates are listed in terminal. On the Silverado, the valve was changed to prevent it from getting dirt inside and causing it to fail. The above is specific to this body style truck only on Chevy and GMC. |
