1994 Mercury Cougar P0402 code

1994 MERCURY COUGAR
140,000 MILES • V8 • 2WD • AUTOMATIC
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VEGASCHUCK
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Hi ....keep getting a P0402 code even after changing EGR valve and all sensors regarding EGR valve including 02 sensors(4) and replacing Gas cap...what are we missing?......last tine we reset code....light came on after driving 1 mile on the next restart.....before that car went 1 week and 100 miles before coming on....
Apr 5, 2010 at 6:09 PM
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DOCFIXIT
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Hi Maybe faulty Differential Pressure Feedback Electronic Sensor. Check vacuum lins for blockage or leaks. If good then DPFE could be faulty.


https://images.2carpros.com/forum/automotive_pictures/198357_Graphic_433.jpg

Hope this helps Thanks for donate
Apr 6, 2010 at 8:08 AM
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VEGASCHUCK
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Replaced DPFE sensor today...reset check engine light...check engine light came back on after 3rd start with P0402 code again after driving 2 miles ( and 3 starts)
Apr 15, 2010 at 3:23 PM
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DOCFIXIT
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Hoses check good? remove EGR valve make sure it is seated. Clean carbon off pintle and passageways.
Apr 16, 2010 at 10:51 AM
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VEGASCHUCK
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Where do I find Pintle valve?
Apr 17, 2010 at 5:40 PM
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DOCFIXIT
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Part of EGR
Apr 19, 2010 at 4:38 PM
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