Smog check fail and ac quit !

[Steve Waddington]

Registration is due, and so is smog, so I went to the 5 min In-and-out, drive-thru smog station. Couldn’t pass. I had just reset my P0455 and the computer knew it (didn’t have a “ drive cycle” I.e. 150 miles on it since. Grrr)

while waiting in line for over an hour with truck running and a/c on...all of a sudden there was a loud whine from under the hood! ( almost like the sound of a horn with a very weak battery)
The smog guy said... “ turn off your a/c”. I did and the noise went away. Turned the a/c on again... and bad noise returned! Shit!
So now I have an 03 Tahoe... unregistered , no smog...and now something wrong with the a/c... in the middle of a pandemic where I’m not allowed to work! WTF!

so even if I fix what’s wrong with the P-whatever code... I have to put 150 miles on it before getting it smogged! AND I have to fix the a/c!
Hope you guys are doing better than me!

 

[treehan77]

Sounds like you have plenty of time to fix it then...check your belts and the a/c idler etc

 

[Tonyrodz]

Sounds like you have plenty of time to fix it then...check your belts and the a/c idler etc

Had the same thing happen on my 03 yrs ago. The idler pulley for the ac locked up. Changed it and it was good.

 

[Rocket Man]

Registration is due, and so is smog, so I went to the 5 min In-and-out, drive-thru smog station. Couldn’t pass. I had just reset my P0455 and the computer knew it (didn’t have a “ drive cycle” I.e. 150 miles on it since. Grrr)

while waiting in line for over an hour with truck running and a/c on...all of a sudden there was a loud whine from under the hood! ( almost like the sound of a horn with a very weak battery)
The smog guy said... “ turn off your a/c”. I did and the noise went away. Turned the a/c on again... and bad noise returned! Shit!
So now I have an 03 Tahoe... unregistered , no smog...and now something wrong with the a/c... in the middle of a pandemic where I’m not allowed to work! WTF!

so even if I fix what’s wrong with the P-whatever code... I have to put 150 miles on it before getting it smogged! AND I have to fix the a/c!
Hope you guys are doing better than me!

You won’t pass until you get your evap problem fixed (P0455 is an evap leak) Parts aren’t too expensive for that. Start with the gas cap and if that doesn’t fix it replace the evap vent solenoid and the evap purge solenoid one by one, clear the code after each part you replace until you don’t get that code returning. Who told you that you need to drive 150 miles? That shouldn’t be the case, just get the codes to clear and a drive cycle should be a half hour or so.

 

[Doubeleive]

time to come up with a side hustle

 

[Scottydoggs]

that code is for a large evap leak. so chances are you have a broken plastic line under the hood. or the filler neck has a vent line, they like to rust out and cause a leak. all of these things can be patched up for less then 10 bucks. vac line to patch a plastic hard line, or cut the rusted out vent line and patch with fuel line and a couple hose clamps.

 

[Steve Waddington]

Is there such a thing as a complete P0455 “ kit”..., where you can buy all the parts that it could be causing the code?

 

[BG1988]

Is there such a thing as a complete P0455 “ kit”..., where you can buy all the parts that it could be causing the code?

you made a mistake resetting the code since it will do a test every 1300 seconds
now without it,
it will be playing wack a mole trying to fix it

 

[Scottydoggs]

smoke test is what you need if you cant see a busted line in the open.

 

[treehan77]

Is there such a thing as a complete P0455 “ kit”..., where you can buy all the parts that it could be causing the code?

No. Even if you replace all the “parts” it still may do it. Mine had the line plugged with charcoal pellets cause the canister broke down. Had to remove the tank and blow all the lines out, replace the vent valve and canister. Some have had luck with a hand vac pump or blowing air into the lines. Check the purge valve on the intake, hopefully you dont see charcoal all the way up there. If not, probably just the vent valve next to the canister itself. It’s like 20 bucks.
If you can’t do this yourself, smoke test is probably the way to start.

 

[George B]

Before you get too far down the parts path you should do some troubleshooting if you are capable. This is where a good scan tool would be a must to do a complete job. Getting a Tech2 would be ideal and in this case be equal in cost to taking it to a dealer to repair it.

There are a few things that could cause the problem on being obviously a large leak through the gas cap or a damaged line. If not that you need to start at the front and work your way back.

This video goes over the EVAP purge solenoid valve troubleshooting. It’s not the same vehicle but the concept is the same. If it fails it never applies vacuum in the first place thus it thinks there is a leak. I have heard of these being cleaned before.

Next is the EVAP vent valve. This one is located under the truck towards the rear of the tank. If it is stuck open the vacuum applied by the purge valve cannot accumulate in the fuel tank so it will see it as a large leak. You can bench test this valve to see if it functions and there are lots of videos out there about that. Here is one for reference.


The last one I will note is the fuel tank pressure sensor. If this gets flaky the computer doesn’t know the correct tank pressure. Here is a video on how they test this. On a suburban you need to lower the tank to reach it.

This is not a complete list of what may be wrong but it is the big three checks with an issue with the canister or lines being right up there too.

A good scan tool is a must if you don’t want to just throw parts at it.

 

[Rocket Man]

Is there such a thing as a complete P0455 “ kit”..., where you can buy all the parts that it could be causing the code?

Sure- buy a new gas cap, purge valve and vent valve if you want to try all 3, or the canister itself. After that if the code doesn’t go away it’s the lines and you don’t need to buy new ones, just blow them out like mentioned.

 

[treehan77]

If yours is as bad as mine was, you’ll find charcoal all the way to the intake. Check that first, it’s easy and free to remove the house from the intake area and check.

 

[treehan77]

Probably not that bad if you can still fill the tank with gas normally though. Make sure the gas cap seal is in good shape too

 

[Steve Waddington]

Well, I had the fuel pump and filter replaced a year and a half ago, and the gas cap around the same time.

I will try to take a look at all the other stuff. Problem is, since my accident last year, I don’t have the flexibility I used to have.( broken femur in 3 places and fractured hip. Two titanium rods and screws holding the left leg together), so getting under the truck might be difficult, but we’ll see.

It’s not the cost if buying the necessary parts that concerns me now... it’s eliminating as many under-the-truck trips as possible! If I could just get all those parts done at once, it would save a lot of pain.

 

[Rocket Man]

Well, I had the fuel pump and filter replaced a year and a half ago, and the gas cap around the same time.

I will try to take a look at all the other stuff. Problem is, since my accident last year, I don’t have the flexibility I used to have.( broken femur in 3 places and fractured hip. Two titanium rods and screws holding the left leg together), so getting under the truck might be difficult, but we’ll see.

It’s not the cost if buying the necessary parts that concerns me now... it’s eliminating as many under-the-truck trips as possible! If I could just get all those parts done at once, it would save a lot of pain.

Then I suggest buying the vapor canister and purge solenoid and replace both of them while you’re under there. The purge valve is on the fuel rail under the hood and can be done after you replace the others or before.

 

[Steve Waddington]

Would you by any chance know those parts numbers for an 03 Tahoe... or tell me where I might find them?
Thanks!

 

[Rocket Man]

Would you by any chance know those parts numbers for an 03 Tahoe... or tell me where I might find them?
Thanks!

Vent valve is ACDelco 2141091, canister is ACDelco 215407.
Rock Auto https://www.rockauto.com/en/catalog/chevrolet,2003,tahoe,5.3l+v8,1412244,exhaust+&+emission

these are not for flex fuel, if you have flex look up the appropriate parts

 

[Steve Waddington]

time to come up with a side hustle

My entire life is a "side hustle" at this point!

 

[Steve Waddington]

Sure- buy a new gas cap, purge valve and vent valve if you want to try all 3, or the canister itself. After that if the code doesn’t go away it’s the lines and you don’t need to buy new ones, just blow them out like mentioned.

And that's exactly how I spent my day today! Ordered all 3 from Amazon...the ACDelco replacement parts.
Pretty easy job actually...except for the stubborn hose clamp tabs on the Vapor Canister Vent Valve (the one under the truck). Still, pretty quick and easy. And just enough clearance under the truck so that I didn't have to jack it up!! Yes!!

So...now I just have to put some miles on it and see if the CEL comes back on. Hopefully not. BTW, in taking off the old parts, I didn't see any debris or charcoal bits coming out of any lines, and no rust underneath anywhere. And I never had any 'slow-fill up' with the gas, so maybe the charcoal canister itself is ok?

Thanks for all the advice and help guys...greatly appreciated!!!