Jump to content

Cause Of Catalyitc Converter Failure? Code 0446


Recommended Posts

Posted

2001 Yukon 5.3l developed rattle after much searching I traced it to the flattened cross over pipe coming from the drivers side going to passenger side. If you hit it with the heal of your hand it will replicate the sound with engine off. Exhaust system seemed to vibrate alot. while running. Had been fighting a trouble code of 0446 and had replaced the "valve" Would this cause a cat failure? We also live on a bad gravel road which clogs the valve could the wash board and pot holes cause the cat failure? Would a bad O2 sensor throw a code? We haven't noticed any real driveability issues either. Not wanting to ruin another cat. Thanks for the help TB

Posted

 

999999995.gifSubject:LR4, LM4, LM7, L59, LQ9, LQ4, L18 DTC P0446 (Restricted/Blocked EVAP Vent Path) Set, Service Engine Soon (SES) Lamp Illuminated (Replace Vent Solenoid and Bracket) #04-06-04-055A - (03/20/2006)

 

 

 

 

 

 

Models:2000-2003 Cadillac Escalade

 

 

2002-2003 Cadillac Escalade EXT

 

 

2003 Cadillac Escalade ESV

 

 

2000-2003 Chevrolet Suburban, Tahoe

 

 

2002-2003 Chevrolet Avalanche

 

 

2000- 2003 GMC Yukon, Yukon XL

 

 

with 4.8L, 5.3L, 6.0L, 8.1L Vortec™ V8 Engine (VINs V, P, T, Z, N, U, G -- RPOs LR4, LM4, LM7, L59, LQ9, LQ4, L18)

 

 

 

 

This bulletin is being revised to add updated warranty information and enhance the content. Please discard Corporate Bulletin Number 04-06-04-055 (Section 06 -- Engine/Propulsion System).

 

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1791752&psdid=210&evc=sm#ss1-1791752">

Condition

Some customers whose vehicles are operated in dusty type environments, such as farming or mining off-road type applications, may comment about the illumination of the instrument panel SES light, with a DTC of P0446 (Restricted/Blocked EVAP Vent Path) being set.

 

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1791752&psdid=210&evc=sm#ss2-1791752">

Cause

Dirt and dust intrusion into the EVAP canister vent solenoid, resulting in restricted air flow, may cause this condition.

 

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1791752&psdid=210&evc=sm#ss3-1791752">

Correction

DO THIS

 

DON'T DO THIS

 

Replace the EVAP vent solenoid with a more robust vent solenoid.

 

DO NOT Replace the EVAP canister or other EVAP parts.

 

After following the Service Manual diagnostic P0446 and determining that the EVAP canister vent valve is the cause of the SES light, replace the existing EVAP canister vent solenoid and bracket. This new vent solenoid has an enhanced filtering capability and a filter element that can be easily removed and cleaned. To ensure correct installation, follow the procedure below.

 


  1. <LI type=1>Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information. <LI type=1>Remove the bolt retaining the vent valve bracket. <LI type=1>Disconnect the electrical connector. <LI type=1>Disconnect the canister vent valve hose. <LI type=1>Install the new vent valve bracket, P/N 15105605, to the vehicle with the retaining bolt. Tighten
    Tighten the bracket mounting bolt to 12 N·m (106 lb in).
     
    <LI type=1>Install the new vent valve, P/N 10382105, to the bracket. <LI type=1>Reinstall the electrical connector. <LI type=1>Reinstall the canister vent valve hose. <LI type=1>Lower the vehicle.
  2. Clear the DTC.

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1791752&psdid=210&evc=sm#ss4-1791752">

Parts Information

Part Number

 

Description

 

Qty

 

15105605

 

Bracket, EVAP Emission Canister Purge

 

1

 

10382105

 

Valve, EVAP Emission Canister Control

 

1

 

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1791752&psdid=210&evc=sm#ss5-1791752">

Warranty Information

For vehicles repaired under warranty, use:

 

Labor Operation

 

Description

 

Labor Time

 

J6441

 

Valve, Evaporative Emission Canister Vent Solenoid and Bracket - Replace

 

Use Published Labor Operation Time

 

THIS WILL HELP WITH YOUR CODE ISSUE. GOOD LUCK :confused:

Posted

Did that repair almost six months ago with little success. Don't know if I would need to clean the thing daily to keep it open or what but I had moved on to service bullitin number one dash 2 : Take roll of black electrical tape from tool box. Cut one piece approximately .75 inches long. Move steering wheel to full down position. Apply said electrical tape to instrument cluster as to cover check engine light. Throw roll of electrical tape vigorously across room so as to avoid crying in front of wife.LOL The evap system wouldn't cause a rich condition to burn up the cat would it? I'm "hoping" the cat gave out do to the same "road" that clogs the evap valve. TB

Posted

Picked the Yukon up from muffler shop and he traced the sound to the Oxygen sensors (little caps rattle). Replaced both sensors and rattle is gone! I asked him about the epoxy thing and he said he hadn't had good luck with it and advised I should change them out. I let him do it for $35 in labor I wasn't about to slide under there on a creeper and mess with them. TB

Posted

I like your electrical tape idea. My light has been on for the same code for about 3 years. I check the codes once in a while to see if anything more important has come up.

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    250.4k
    Total Topics
    2.7m
    Total Posts
  • Member Statistics

    342,842
    Total Members
    8,960
    Most Online
    CaptainDad
    Newest Member
    CaptainDad
    Joined
  • Who's Online   5 Members, 0 Anonymous, 487 Guests (See full list)

  • Latest Articles

  • Posts

    • I like the idea.  I would pick diesel if I had a choice. I need pictures though.
    • I've installed cheap eBay new aftermarket digitizers before.  They work.  Did a bunch of Cadillac CUE (aka Cadillac's MyLink) for someone years ago.  They all worked fine after the repair.    That number 22740886, that is a component part # for GM.  You can use it to search, but its not something that's obtainable at the dealer level.     So pretty much any of these will work - 2015 Colorado Digitizer for sale | eBay
    • Black bumper and the later years Z-71 style color matched grille.
    • You can install tailpipes that direct the exhaust sideways vs the OEM one that goes straight back. There are several on the market, do you own research. HOWEVER, you need to make sure the Venturi vents are still intact, otherwise it will throw a engine code. There is a sensor somewhere that detects back pressure on the exhaust. And if it doesn't collect the correct metrics, it will throw the truck into limp mode. 
    • "Teardown" is complete. Head surfaces are clean and ready, new intake is prepped and ready. Coolant drained and water pump is removed, radiator is removed, new hoses and pump are ready.   The replacement intake is also from a '95 (with I think 260k, the odometer said). Noticeably less pitting where it covers the rear coolant passages. I'm not sure if that's a tribute to more frequent use, more frequent coolant changes/upkeep, or if the intake was machined at some point. But it appears I found a good one.   My coolant hoses were original, and the lower hose still retained the factory spring inside. It's not really rusty, but it's got deposits all over it. Unsure if I should re-install it (will thoroughly clean it first). Someone said hose technology has gotten better since 1995 (has it?) and I don't need the spring. I think modern EPDM is what made those hoses last from 1995-2026, so it's a question of how much suction can the water pump really pull, and will it collapse the hose without a spring?   I'm stopped and waiting for parts, however.   When I first brought the truck home, the fan was intermittently hitting the radiator shroud. I could see someone had monkeyed with the shroud (put a bunch of cardboard as a spacer between the upper/lower shroud halves. Someone said the motor mounts have likely failed and the engine has sagged. I wasn't sure I believed that. The engine is really solid in its mounts: To remove the old intake I *just* nearly permanently welded to the heads with freshly cured RTV and gasket snot two weeks ago, I literally had to use the arms on my lift and a chain with a bolt attached to the intake to pull it loose. It almost picked the front of the truck off the ground before ....scuuuuuuuuuuup.... I could actually hear the gaskets tearing and it broke loose and the whole truck settled back down. Motor barely moved.   SO, those parts I'm waiting on... The lower radiator mounts/bushings had completely failed. The radiator needs to be insulated from the rad support, and the bushings help the rad stand at the correct height. The plastic "baffle" was also destroyed at some point. Someone had attached the shroud to it incorrectly, overlapping a joint that should have been underlapped, creating another suspect issue potentially causing things to hit the fan. Broken tabs, side is busted off, and it's perma-formed/bent where it was jimmied incorrectly.   The baffle? Unobtainum. Long since discontinued from GM, of course. Aftermarket/capa/chinese? Also unobtanium. In GM's infinite wisdom, it appears there are at least two different variations whether the Blazer is 2 or 4 door, and I can't yet tell if they shared the same part with the S-pickups. Plan B, if I can't find a viable used one, will be to create a bracket to re-assemble the critical joint I need to seal a gap with the shroud. But that will bug me, it won't be...perfect.   The water pump bolts appear to have been installed with...plumber's putty. I guess, sure, if it works...? I've found a few "backyard fixes" like that. Someone's been here before....   If I can't find someone to jam bamboo under my fingernails to fill my free time this week I think I'll install the driver's power window motor and replace the rear door speaker that's inop. I've got a genuine GM "9.5" ohm working replacement. Why GM used a non-standard resistance....nevermind. Of course they did, you can get more sound from a cheap factory amp that way.   And the saga goes on...
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...