Dreaded PO441 Error Code - Fix

I've had my Tacoma now for 6 years without a problem. Last Saturday while on a short trip, the CEL light came on. My process to cure this is the basis for this post. Hopefully it will assist you in fixing your CEL and saving a few bucks. Photos are embedded as links and attached at bottom.

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I hooked up my Innova unit and pulled the code. A PO441 Evaporative Emission System Incorrect Purge Flow.

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I did some research and found that three components could be the culprit. Bad Gas Cap, Control Valve, or Canister. This was provided there were no rotted or defective hoses. I checked all of my hoses and they were all good, and supple. I ordered a new Gas Cap from Toyota. It was $30. It was a quick install.

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I used the Innova to reset the code and get rid of the CEL. I drove the truck for about 2 days before the CEL reappeared.

I was not going to spend the cash for a Charcoal Canister unless I was sure it was the problem. So I stopped by my local dealer, Price Toyota, and they ran diagnostics for $99. It was the Control Valve, and it had to be ordered. I ordered it and it was in the next morning. They allowed me to do the install and part order to save me some money. I avoided the mark up on the price of the part and the labor cost.

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The Valve is very easy to get to, its right on the side of the intake assembly.

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You'll need a 10mm socket. Remove the screws to the intake cover and prop it up. Now you can clearly see the valve.

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You do not need any tools to get the electrical connector off, and the hoses, the one clamp you can do by hand. Remove all connections.

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Use a 10mm socket to remove the lone bolt on the bottom and remove the old valve. It does not look bad and there is no way to open it to try a cleaning.

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Install the new valve using the lone bolt snugging it up a little.

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Hook up your hoses and electrical connection, takes all of 30 seconds.

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Secure your intake cover and close the hood, your done here. Hook up the Innova and clear your code.

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This worked for me and I avoided the expensive Charcoal Canister which is up under the bed of the truck, and is quite expensive and not available as an aftermarket part.

Hope this helps with your PO4441 CEL Code. This Valve fits multiple vehicles from 2004 to date.

Dave

 

Canister runs around $360. Rock auto has them and so does AutoZone. Well special order, but hey are available. I've got a p0175/172 light, so in running way rich and my ultra gauge tells me as well. I don't think this control valve is MY problem, but it very well could be. I'm leaning more towards and leaking injector in my case.

Anyways, good info and if I ever run across this, I'll be sure to come back to this thread!

 

This might save someone some time & $$. Got the code - cleared it - came back - put silicone grease on the rubber "0" rings on the gas cap and on the top of the filler tube where the cap seats - no more code.
Had this is my arsenal
http://www.grainger.com/Grainger/LOCTITE-Silicone-Lubricant-5E201?Pid=search