P0446 Code on Cadillac, Chevrolet, & GMC Full-Size Utility Trucks
GM has issued a TSB (#04-06-0055) for code P0446 on 2000-03 Cadillac, Chevrolet and GMC full size utility trucks.
The charcoal canister stores gasoline vapors from the tank. When certain driving conditions are met, the computer supplies power to the purge and vent solenoids. The purge solenoid opens the vacuum line between the canister and the intake manifold and engine vacuum sucks the vapors out of the charcoal. The vent solenoid opens a fresh air line into the canister.
If these vehicles are driven in dusty conditions, road grit and dust can accumulate in the vent solenoid resulting in a restriction. That will set a P0446 code.
The fix is to replace the vent solenoid and bracket with a newer design. Remove the old vent valve bracket and install the new bracket (part #15105605) and a new vent valve (part # 15750484). Then, clear the trouble code.
For more information on this repair or any others for your vehicle, buy an online subscription to either Alldatadiy.com or eautorepair.net. Click on this link to compare the two services: Compare Alldata and Eautorepair.
If you just need information for a single repair and want to save money,eautorepair offers a lower price 1-week subscription for only $11.99. Or, if you’ll be working on this vehicle in the future, you can buy a 1-year subscription (Alldatadiy.com for $26.99, or eautorepair.net $29.99)
© 2007 Rick Muscoplat
Alldatadiy.com
eautorepair.net
Both Alldata and Eautorepair offer professional grade shop manuals at a price you can afford. Check them out!.
Hover your mouse over the REPAIR ARTICLES tab at the top of the page. The click on DIAGNOSTICS to search by SYMPTOM, TROUBLE CODE, or read TECH TIPS on how to diagnose a problem
Click on MAKE an MODEL to see all the articles I’ve written for your vehicle
Click on REPAIR TOPICS to read individual articles written for specific automotive systems
If you’ve had your car scanned and know the trouble code go to TROUBLE CODES
Here are some quick links to speed up your research
Click on the link below for speedy navigation:
ABS issues, how to bleed ABS brakes
Alternator issues or how to test
Belt diagram or serpentine belt issues
Brakes, brake issues, what kind of brake parts to buy, ABS issues
Car Alarms or Antitheft systems
Cooling system, Water pump, What type of coolant to use
Firing order, cylinder layout, finding #1 cylinder
Oxygen sensors, How they work, How to change, How to test
Window issues, power window motor, replace window regulator, glass adhesive
What year, make, and model are we talking about? They’re located in different places on every vehicle.