Mechanics

CHEVY CODE P0171

1999 Chevrolet Silverado

Computer problem
1999 Chevy Silverado V8 Two Wheel Drive Automatic 371000 miles

I own a 1999 Silverado 1500 5.3L V8. All the oxygen sensors, MAP, and MAF sensors have been replaced in the past 5-6 months. Every few days I get the code P0171 lean on bank 1. What should I do next to correct the problem?
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Lbolton
March 15, 2009.



You may have a vacuum leak, get a can of spray throttle body cleaner, spray the vac lines and maniflod area, when the idle changes, youve found the leak! You want the engine running and spray on the outside but do direct the stream onto the hoses, if it is a vacuum leak, the engine idle will change speed, then you have detected a leak, repair the vacuum leak and see how it runs! also check the ECT(engine coolant temp) sensor.


http://www.2carpros.com/forum/automotive_pictures/62217_CRC_Throttle_Body_16.jpg


Merlin2021
Mar 15, 2009.