Question about 2004 GMC Sierra

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2004 gmc sierra

Hi a code p0102 came up should i replace the sensor or can someone tell me how to test the sensor

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  • oksmitty Apr 07, 2009

    I have the same code on a 1997 4.3 Vortec PO102 It skips after two COMPLETE tune ups at rpms over 1500 worse on wet days.The Plugs all are sweet looking. Your tests are good but can we go deeper into the output of the MAF?

    ok after that can you clean the probe with Alcohol? What is the out put on the third wire? Volts or milliamps ? Can you get in series with the output and monitor the output volts or amps over a rpm range????Or is it a digital output???



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P0102 is mass air flow sensor circuit, low input the MAF is attached to the air cleaner where the hose runs out of it... Unplug it and check the voltage supply and the ground... looking into the plug, with the tab facing up, there will be 3 connecters inside it, left to right they are.... sensor signal, ground and supply.... make sure you have 12 volts at your supply and the ground is good good luck

Posted on Feb 28, 2009


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1996 gmc sierra 5.7L what would cause engine codes p0102, p0108, p0121,p0300 at same time?

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Thank you for using fixya and note that Auto Zone and most larger auto parts store will scan DTC codes free of charge.

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Trouble shooting

this is OBD 2 and u will need a scan tool to access trouble codes, this system started in 96, on old pre 96 system u could blink the check engine light and get the code. U CAN GO TO ANY KRAGEN OR AUTOZONE AND THEY WILL TEST THE SYSTEM FOR TROUBLE CODES FOR FREE.

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