Jump to content

Po440 And Po449 Codes

llihkao

By llihkao
in Ask A GM Technician

Recommended Posts

llihkao New Member

llihkao

Posted
Posted

I have a 1999 GMC Sierra 4WD extended cab pickup with a 5.3L Vortec engine. The "service engine soon" light comes on and when I read the computer, codes PO440 and PO449 appear. The "ses" light stays off for a short time after I erase the codes, then it reappears. Someone please tell me what I need to do or replace in order to eliminate this problem. Also, my truck experiences terrible hesitation whenever I first drive it after it has set for a few hours. It acts like it is not getting enough fuel. This problems goes away after about 60 seconds of running the engine. Are these problems related? Thanks.

ruddy Enthusiast

ruddy

Posted
Posted
I have a 1999 GMC Sierra 4WD extended cab pickup with a 5.3L Vortec engine. The "service engine soon" light comes on and when I read the computer, codes PO440 and PO449 appear. The "ses" light stays off for a short time after I erase the codes, then it reappears. Someone please tell me what I need to do or replace in order to eliminate this problem. Also, my truck experiences terrible hesitation whenever I first drive it after it has set for a few hours. It acts like it is not getting enough fuel. This problems goes away after about 60 seconds of running the engine. Are these problems related? Thanks.

 

Try this site: http://www.obd-codes.com/trouble_codes/

LowRyter Enthusiast

LowRyter

Posted
Posted

I have a 1999 Chev 2500, 6.0L, I got a service engine light. Code reader listed 440:

 

Evaporative Emission System (EVAP) small leak/no flow condition

Probable Causes:

a) Defective or loose fuel cap

b) EVAP Canister or hose cracked- not connected

c) Purge or vent solenoid defective

d) Vacuum leak at engine.

 

Let me know if you get a fix. I could use it.

Indy Enthusiast

Indy

Posted
Posted

TSB: 04-06-04-055a should cover it. Probably need vent solenoid 103821050 and bracket 15105605. It's a common problem with dirt in the Evap valve on top of the gas tank. I've had code PO449 and PO452 for about 5 years now, never got around to fixing it yet. It does not cause any driveability problems at all. If your truck is running poorly, it's not related to code PO449.

The code resets on the second drive cycle. If you read the code after the first drive cycle you will get PO449 code pending.

Krambo Enthusiast

Krambo

Posted
Posted
TSB: 04-06-04-055a should cover it. Probably need vent solenoid 103821050 and bracket 15105605. It's a common problem with dirt in the Evap valve on top of the gas tank. I've had code PO449 and PO452 for about 5 years now, never got around to fixing it yet. It does not cause any driveability problems at all. If your truck is running poorly, it's not related to code PO449.

The code resets on the second drive cycle. If you read the code after the first drive cycle you will get PO449 code pending.

 

:smash: Agree. Your engine stumbling is not related.

  • 3 months later...
BIG BEE New Member

BIG BEE

Posted
Posted

My 99 is doing the same things, I changed the fuel pressure regulator and the stumbling has gone away. I still need to replace the vent solenoid

Archived

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

Go to topic listing

  • Latest Articles

  • Posts

    • Gkistler
      2015 Sierra Denali L86 cyl 5 misfire at idle

      By Gkistler · Posted

      Hi friends - first time poster. I have a 2015 sierra Denali with 150k miles, I’m the second owner and she’s given me 75k of great service. I run a pulse AFM disable device. Starting Thursday when I exited the freeway after a short local ride it started idling rough, with an obvious misfire shake and was down on low end power.  I got it home and hooked it up to my scannner and found no codes but in live data a pretty bad misfire on cylinder 5. I replaced the coil, plug and wire with all new OE replacements (Delphi gn10165 coil, acdelco wire and 41-168 plug). It’s still behaving the same way after firing the parts cannon at it.   I know cyl 5 is a non AFM cylinder so I am not thinking this is AFM related but I’m kinda at a loss. injector? Bent pushrod? It’s running too well over 1k rpm to suggest those IMO. Has anyone chase this issue before and what was it? Any suggestions? 
    • zibzer2
      Pulsating Noise 4Cyl Mode

      By zibzer2 · Posted

      2017 Silverado L83 5.3l 6speed transmission Hello, not a new member but havent posted in a while and my old signup info isnt working so had to create a new account. anyways, I have an issue with my truck and hope someone can spread some light on whats happening: -when it goes to 4cyl mode it makes a clunk sound (but not when coasting or going downhill) -when in 4 cyl mode and under load it makes a load pulsating sound (not a tick). -goes away completely when in M5 gear or when plugging in an AFM delete. Im guessing it is one of 2 things but im not convinced of either to be honest. 1. lifter stuck in v8 mode 2. torque converter shudder realistically it doesn't seem like the TC as there is no physical vibration , and it never happens in v8 mode. but maybe? and wouldnt a lifter make a sound whether with load or not? any ideas let me know please. thank you!  
    • Chuck FB
      Some Assembly is Required

      By Chuck FB · Posted

      Which has made me wonder with the various engine failures of a few brands in the last few years, is it sub par materials such as lifters etc causing failures, or bearing clearances on the crank etc or perhaps bad designing of an engine physically or causing too much load on the components due to the hp/torque they can push out of them. Or is the oil viscosity and additive package of current oils or a lack of oil flow by an oil pump not able to supply sufficient oil at idle or under high load at low rpm. Or is it every item I listed that combined together has pushed the limits so far to the left that there is hardly a margin of safety left and add in some fuel dilution and too long of an OCI and premature engine failure is the result ?. 
    • Grumpy Bear
      Some Assembly is Required

      By Grumpy Bear · Posted

      He is not saying that an SAE *W20 will have more viscosity than a *W40 due to MORE VII polymers. He is saying that although multiple *W40 may post in the PDS the same or similar 100 C and 150 C viscosities that the blenders choice of modifier TYPE and AMOUNT to get his chosen base to grade will not give identical real world viscosities in shear and at temperature. All will pass the SII test but not all will pass the 100 C HTHS (unpublished value) testing the blender does and relies on to get the required by law "percentage improvement' referenced to his last great work.    Tis the problem with the lie. Once told others are required to support it. 
    • PunchT37
      Parking Brake - Automatic Engagement Questions

      By PunchT37 · Posted

      I have a `25, 1500 that auto sets on incline. Never knew that at first. I have the electronic shifter. Just think if it didn`t do that? Unlike a mechanical shift that you can muscle out of park, how would you get this thing out? That would be a problem.   What I found out later is, I don`t have to push the button to release. Just put it in gear.   Setting parameters? Don`t know if it`s possible.

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...