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2002 Chevrolet Tahoe Question: Codes P0171 & P0174
Answer #1pushrod February 01, 2013, 21:52Master
Replypowell, February 02, 2013, 03:25Rookie
Replypushrod, February 02, 2013, 04:12Master
First suspect is vacuum leak at intake manifold. Not the only possibility though. Prob. need to get a mechanic to check it out.
Replypowell, February 02, 2013, 04:17Rookie
I work part time at a shop. can it be check with carb spray
Replypushrod, February 02, 2013, 04:33Master
Cool, now we can talk motors! Yes that will work, check all the other stuff also like MAF may need cleaning, upstream O2's
Use a scanner, you will find it!
Replypowell, February 02, 2013, 04:35Rookie