1995 gmc jimmy nox gas to high on emissions test! Do I have a bad or pluged egr valve! msgtmorgan
Jan 29, 2011 at 3:00 AM
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JACOBANDNICKOLAS
AUTOMOTIVE REPAIR CONTRIBUTOR
110,190 POSTS
Either one could cause it. If the vehicle hasn't been tuned up for a long time, that would be a good place to start. Also, have the oil changed before the next test if it is due or near due. If a tune up doesn't help, then I would remove the EGR and check to make sure it isn't carboned as well as the intake where it mounts.