found what turned out to be a common problem. my 06 1500 (54k miles)gave a 0449 Evaporative Emission Canister Purge Solenoid trbl code. behind fuel tank, attached to bed, there is a round black plastic can, with a hose and wiring connector. the plastic can's top can be removed and will probably have a lot of dirt in it. the solenoid can fail and mine metered open at 1.5 mohms. the new one was 20 ohms. part was $27.
it was not the fuel cap. the canister can be cleaned, if your in a dusty enviroment- I would check it. hope this helps save some one else some money.
94 c3500, 6.5td, 4l80e rebuilt, relocate pmd, heath chip, lp and x-over pipe, 97 cooling upgrade, afe cold air intake, marine injectors, bypass ops, guages-tranny temp,egt,boost,fuel press-aux fuel tank, 410 changed to 373 gears, 4" sraight exhaust w/new down pipe, modified fuel cap, high idle switch, second tranny cooler, battery mod, gm-8 w/homemade t/m
2006 1500 suburban 4wd, 5.3l stock.
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