2006, 232xxx, 2.4L

I've been getting a p0446 for ages now and I've replaced the rear evap and the front evap parts and the gas cap (using the information from this website and those part numbers). Never went away. But alas, now I have a p0302 and even though it says it's a misfire I don't feel it shudder. I've swapped the coil packs and the spark plugs to see if it moved and it has not. I sometimes smell gas but not very often when exiting the car. The p0446 is only a "pending fault" and always has been, I've never checked it and it be a current fault, however it still illuminates the CEL. When the p0446 is not present and only the p0302, sometimes the CEL will go out on it's own, but then shows back up. Here is two separate freeze frame data figures I've pulled from the p0302.


Vehicle VIN: 3GNDA23P56S515233
Vehicle Manufacturer: Chevrolet
Vehicle Calibration ID: 126

Freeze frame information:
------------------
Fuel Status = 0 byte
Engine Load = 31.373 %
Engine Coolant Temperature = 195.8 °F
Fuel Trim Bank 1 Short Term = 1.562 %
Fuel Trim Bank 1 Long Term = 7.031 %
Intake Manifold Pressure = 5.802 psi
Engine RPM = 772.75 rpm
Speed (OBD) = 0 mph
Timing Advance = 6 °
Intake Air Temperature = 127.4 °F
Mass Air Flow Rate = 3.66 g/s
Throttle Position(Manifold) = 23.529 %
Run time since engine start = 655 s
Fuel Level (From Engine ECU) = 72.941 %
Evap System Vapour Pressure = -4,107.5 Pa
Barometric pressure (from vehicle) = 14.359 psi
Catalyst Temperature (Bank 1,Sensor 1) = 1,074.2 °F
Voltage (Control Module) = 12.824 V
Engine Load(Absolute) = 20 %
Commanded Equivalence Ratio(lambda) = 1
Relative Throttle Position = 12.549 %
Ambient air temp = 111.2 °F
Absolute Throttle Position B = 23.922 %
Accelerator PedalPosition D = 19.216 %
Accelerator PedalPosition E = 9.412 %


End of report.


Vehicle VIN: 3GNDA23P56S515233
Vehicle Manufacturer: Chevrolet
Vehicle Calibration ID: 12607442

Freeze frame information:
------------------
Fuel Status = 0 byte
Engine Load = 40 %
Engine Coolant Temperature = 192.2 °F
Fuel Trim Bank 1 Short Term = -3.906 %
Fuel Trim Bank 1 Long Term = 7.812 %
Intake Manifold Pressure = 9.572 psi
Engine RPM = 2,051 rpm
Speed (OBD) = 17.398 mph
Timing Advance = 27.5 °
Intake Air Temperature = 109.4 °F
Mass Air Flow Rate = 18.23 g/s
Throttle Position(Manifold) = 35.686 %
Run time since engine start = 1,033 s
Fuel Level (From Engine ECU) = 25.098 %
Evap System Vapour Pressure = -4,105 Pa
Barometric pressure (from vehicle) = 14.359 psi
Catalyst Temperature (Bank 1,Sensor 1) = 1,373 °F
Voltage (Control Module) = 13.845 V
Engine Load(Absolute) = 37.647 %
Commanded Equivalence Ratio(lambda) = 1
Relative Throttle Position = 24.706 %
Ambient air temp = 104 °F
Absolute Throttle Position B = 36.078 %
Accelerator PedalPosition D = 27.059 %
Accelerator PedalPosition E = 13.333 %


End of report.

 

You can get a loaner compression tester at your nearby auto parts store. With that many miles, it may be a mechanical problem. Post your test results here.

 

Will be able to Wednesday.

 

Check the fuel pressure and vapour lines , from the front of the rear tire on the drivers side

 

Okay, here is the data for the compression test:
163/160/153/165

fuel pressure test:
57psi

While I was there, I cleaned and swapped the fuel injectors around to see if it would make a difference and put new spark plugs in. This time I didn't put anti seize on the threads

The lines from the canister look okay but I found this, looks like someone tried to use it as a jack point.
one thing I forgot to mention is that lately when getting gas the fuel pump shuts off early. This is a new development that started just a month ago.

 

Wow - those plugs are toasted. The deposits around the whisker/center are odd - I've never seen that before. The new plugs were definitely in order.
(swapping the injectors and plugs were a great way to help the diagnosis - a lot of people spend unnecessary $'s and install a new injector or such)

The compression readings are within specs I think - the no. 3 cyl is a bit low - maybe someone else can spell out the actual specs for that.

That's the gas tank that is bent? Wow -

 

Did I see something about premature fuel fill cut off? That comes from the P0446. The EVAP vent is not opening or the tube is bent (small tube next to the filler neck).

That is the floor pan that is bent.

Why is there a washer on #4? The compression should be within 15% of each other.#3 looks like the one with the miss, but #2 is not far behind.

 

No wonder with the tank compressed like that.
plugs look nasty but just a little carbon , perhaps a Seafoam treatment to clean up the cylinders

 

The Purge valve was replaced 10-26-18 @ 211949 miles. I did a seafoam treatment (the spray at throttle body) on 8-11-19 @ 239446 miles

 

I dunno what that washer thing is I just noticed it. went and grabbed the plug, it flaked off... hope its not part of the housing! it was a little more difficult to remove than the other plugs...