P0410 A different cause

roadrunner · Post by **roadrunner** » Thu Dec 06, 2007 4:01 pm

I've been reading with interest the threads regarding this code and have experienced it myself. Have done all the air pump stuff stated in the tsb and still had intermittent return of engine light caused by PO410. This would happen even after the truck had been running for several hours. I reasoned there must be another cause since the pump only runs during initial warmup. (I bought and was carrying a code scanner with since I'd been having so much trouble with light coming on.) What I discovered was a plugged emission filter under the truck. On my 01 crew it is located at the front edge of the box underneath directly above the driveshaft and has a one bolt bracket holding it on with a two wire connector and an approximately 1/2 inch hose hooked to it. Upon taking it off and apart I discovered it was full of mud and dirt and dust. I cleaned it all up and reinstalled and haven't had any more incidence of P0410 since. I also had replaced the gas cap as I was told by GM this could also cause this code which didn't have any effect on it at all. Hope this helps somobody else too.

Post by **HenryJ** » Thu Dec 06, 2007 4:31 pm

This one- Evap Vent Valve Filter?

roadrunner · Post by **roadrunner** » Thu Dec 06, 2007 6:36 pm

Yup that's the one. Careful when cleaning out the valve as it is easy to loose or damage the little rubber disc that is spring loaded inside and acts to seal it off in neutral position.

mudtaxi · Post by **mudtaxi** » Thu Dec 06, 2007 6:38 pm

if thats where i think it is i dont just have a small thing like that i have a big black box looking thing could it be the same thing

Post by **HenryJ** » Thu Dec 06, 2007 6:42 pm

The big black box is the charcoal canister.

roadrunner · Post by **roadrunner** » Thu Dec 06, 2007 7:07 pm

The "big black box" sits off to the right side more directly above and behind the gas tank. The Evap vent valve is attached to the crossmember directly above the driveshaft. HenryJ has a link above which gives a great picture of the thing if you want to click on and go see.

Post by **HenryJ** » Thu Dec 06, 2007 7:28 pm

Edited your title P refers the the PCM and is followed by a number designating the fault code. By using an "O" instead of the numerical "0" your thread did not show up in a search. There is quite a bit of information available on the P0410 fault code.

roadrunner · Post by **roadrunner** » Thu Dec 06, 2007 7:36 pm

Ooops, sorry! I tend to do that a lot when typing numbers and letters together.

Post by **HenryJ** » Thu Dec 06, 2007 7:41 pm

While I do understand that you had this code, I do doubt that the evaporative vent valve had anything to do with this code. P0410 deals with the secondary air injection pump. Codes involving the evap vent valve start at P0440 and go numerically higher.

The two systems do not interact, hence my skepticism.

roadrunner · Post by **roadrunner** » Thu Dec 06, 2007 7:47 pm

I can understand your skepticism but I had tried all manner of other fixes including replacing the gas cap (a GM tech suggested that one) and so far cleaning out the evap valve has yielded 3 plus weeks with no recurrence of P0410. Previously I would set this code 3-8 times per week. Doesn't make much sense to me either but I can't argue with success. At least I now feel like I can safely leave the scanner home.

Post by **HenryJ** » Thu Dec 06, 2007 7:50 pm

If the dealership recommended a gas cap the code was likely a P0440, or P0442. Those deal with the system being unable to bleed up tank vacuum, indicating a leak.

roadrunner · Post by **roadrunner** » Thu Dec 06, 2007 8:02 pm

Won't argue with ya. Don't know why they said gas cap. It's working now so unless it goes on the fritz again I ain't foolin with it.

JaVeRo · Post by **JaVeRo** » Fri Dec 07, 2007 3:46 am

I don't remember the code but I had a code set that had something to do with the evap system.

The problem was the wires that are attached to the crossmember directly below the front driveshaft. They were buggered up pretty bad from sticks and limbs. I spliced them back together with solder, heat shrink and sealer and rerouted them above the driveshaft.

It may not be your problem but would still be worth checking, especially if you spend any time offroad or running thru pastures.

James

roadrunner · Post by **roadrunner** » Fri Dec 07, 2007 12:31 pm

I have examined the wires you speak of but don't know what or if they would set a code as on mine they are the encoder wires for electric 4x4. And yeah they are in a lousy place from the factory. I don't get offroad much but out here the roads are so bad in winter I would probably have better luck driving in the pastures. Last winter I had to use my CC from Wed before Christmas till the 9th of April and spent a bundle on repairs during that time. I also discovered lo 4wheel really does have a use other than rock climbing when the roads get bad enough! Also thank god for BFG all terrain tires!

JaVeRo · Post by **JaVeRo** » Sat Dec 08, 2007 7:37 am

roadrunner wrote:I have examined the wires you speak of but don't know what or if they would set a code as on mine they are the encoder wires for electric 4x4. And yeah they are in a lousy place from the factory. I don't get offroad much but out here the roads are so bad in winter I would probably have better luck driving in the pastures. Last winter I had to use my CC from Wed before Christmas till the 9th of April and spent a bundle on repairs during that time. I also discovered lo 4wheel really does have a use other than rock climbing when the roads get bad enough! Also thank god for BFG all terrain tires!

That's what I thought originally but I have to respectfully disagree. There is a plug mounted at the top of the transfer case and by unplugging it, you can reroute the wires above the front driveshaft. I tied mine to the fuel lines. I honestly don't believe these are the wires going to the encoder motor. I could be wrong, my wife say's I usually am.

James

roadrunner · Post by **roadrunner** » Sat Dec 08, 2007 7:03 pm

Sure sounds like you are speaking of the encoder wires . They have a plug-in on the housing which is part of the encoder motor. On my 01 there are no other wires in that particular area. Some encoders have a pig tail mine doesn't the harness plugs directly into the encoder switch and could easily appear to be part of the transfer case but is not. It is part of the housing which is part of the encoder motor/switch assy.

JaVeRo · Post by **JaVeRo** » Mon Dec 24, 2007 1:46 am

Something else that may be worth checking. There is a vent hose from the fuel tank to the EVAP system that was rubbing on the cab of my crewcab. I found it when I was putting in a new fuel pump. It appears to have been routed based on an extended cab body and the same parts were used when the crew was built.

This shows the general location with the fuel tank removed, it's the hard plastic tubing at the top of the picture.

This shows where it was rubbing. Mine was almost worn thru. I replaced it with a rubber fuel hose and clamps.

This was over a year ago and I don't remember all the details. If it doesn't help you, maybe it will help someone.

James

roadrunner · Post by **roadrunner** » Mon Dec 24, 2007 2:51 pm

Interesting. So far no additional codes. Is this evap hose visible/accessible with the tank in place? I'd hate to have to pull the tank to check.

quickbiker · Post by **quickbiker** » Mon Dec 24, 2007 7:48 pm

Check this thread.. What I had to do was to replace the air pump, check valves (2ea), and the fuse.

roadrunner · Post by **roadrunner** » Tue Dec 25, 2007 5:45 pm

Interesting read and a good thread. My pump was replaced shortly before I bought the truck. (I suspect previous owner was having troubles too) Fuse is okay. Check valves are shot and currently blocked off till I can get them replaced. All else is okay and has revised relocated hose on already. I agree the hose is not located in a very good place. Seems like it might pick up snow or water spray from that big clutch-fan rather easily so I moved it to a more obscure location.