Mechanics

EVAP CODE PO442

1997 Chevrolet Malibu • 6 cylinder FWD Automatic •

1997 Malibu, CODE PO442 I know that is small leak in evap. Do you have a diagram for it? Components and wiring.
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GM Fixer
July 25, 2011.




The first thing I would check was your gas cap tight?Also remove the gas cap and look at the seal on the cap is it cracking if so I would replace the cap clear the code and see if it comes back. The problem with diagnosing this code your self is it requires a nitrogen and smoke cart also a tech2 scan tool with the correct soft where to close the evap system so you can first charge the system with nitrogen and if a leak is detected put smoke in and look for a leak. Also need the scan tool to open and close the vent solenoid and operate the canister purge solenoind thru the computer to see if there working. Betime you by all this equipment and learn how to use it it would be cheaper just to have someone look at the car and diagnose it.

Saturntech9
Jul 25, 2011.
Dad put on a new gas cap OEM with VIN the light came back on but with a code P0113 NEW CODE. My code reader states that there is a problem still with the evap system. No code yet. It would be nice to have schematics for EVAP SYSTEM.

Tiny
GM Fixer
Jul 27, 2011.
If there is no evap code how do you know there is a problem with the evap?Does your code reader say evap monitor not ready?Thats normal because you just had the code and cleared so it will reset the monitors and they will have to be reset. If your not needing a smog soon no worries the monitor will reset will you drive over time. So was there a problem with the cap is that why it was replaced?Also the code P0113 is inlet air temp sensor circuit high voltage. Does your code reader display engine live data?If so what does your iat sensor show for temp?

Saturntech9
Jul 27, 2011.
My code reader also has LED's Green Yellow Red and yellow is on which tells me that there is a wire/or solenoid that is faulty. I had just gone through a pile of work on my truck and now I finnally have a green light. Truck code was P0455 I changed the evap canister vent solenoid and right away I have a Green light and now NO PROBLEMS! Yah!
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Tiny
GM Fixer
Jul 27, 2011.
What make and model scanner do you have all the scanners I have seen with those lights are only for a quick check to see if the o2 EGR EVAP etc monitors are set or not. There not to tell of a circuit fault there just to tell you if the monitors are set. If there was a circuit fault or failure it would set a code for it.

Saturntech9
Jul 27, 2011.
Innova model 3030 works well for me but it would be nice to get an on-line scanner. P0113 came back on, so I guess I will replace the sensor

Tiny
GM Fixer
Aug 2, 2011.
I have noticed that some gas doesn't even smell like gas anymore, some have a turpentine smell to it. Just all depends wher ya go.

Tiny
GM Fixer
Aug 2, 2011.
Does your scanner read live data?If so what does your inlet air temp sensor read temp wise?Most of the air inlet temp issues I have seen have been the connector or wires to it and not the sensor but anything is possible.

Saturntech9
Aug 2, 2011.
Just looked up your scanner I was right those lights are for your monitors to tell you if there set and your car is ok to take to try to smog it. Its nothing to do with the wiring for your evap system it just means you have to do the drive cycle to set the monitors that arent set. Doesnt look like it will read live engine data.

Saturntech9
Aug 2, 2011.

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