Carbon/Charcoal Canister

QuestAvMan · #1 02-28-2006, 09:19 AM

My service engine soon light came on, so I went and had the code checked at Checker's Auto....

The gentleman said the code was for my Carbon/Charcoal Canister???????

He told me my fuel mileage was going to go to crap..WHICH IT HAS!

What do I need to do, and what are some possible fixes, and costs any of you have encountered...Thanks for your help!

John
South Dakota

billibong · #2 02-28-2006, 09:28 AM

The charcoal cannister, or evaporative emissions control canister, is located in the quarter panel area behind the rear left wheel.
Your first step should be to check the canister and the lines running to it to make sure there aren't ane clogs or cracks in them. Are you noticing any kind of a gas smell around the car at all?
The swap out is fairly easy, just unbolt and disconnenct the lines and replace it. Just make sure to check the lines and replace any that are looking worn out with the same type rated at the same level as the original ones.

2kTrailBlazer · #3 02-28-2006, 10:23 AM

If im not mistaking that code can lead to several different parts that need replaced...u may want to talk with the dealer

blazee · #4 02-28-2006, 10:46 AM

Do you remember what the code is? If not, I'd suggest having it read again, before you do anything. Taking the guy's word that there is something wrong with the canister is risky, most of the guys don't know what they're talking about.

Please include the vehicle information in your next reply.

QuestAvMan · #5 02-28-2006, 11:35 AM

Its a 1996 Blazer.....4.3 L V6
I do not remember the code, but he cleared it out, so I dont know if it can be re-read
I will have to take a look at it and try and figure something out...what are some other common problems, that can relate to the Canister??

Still confused in South Dakota

Thanks in advance
John

scholzee · #6 02-28-2006, 12:59 PM

On mine the vent solenoid was not opening and venting the system, on my 2dr this solenoid is up between the rear axle "pumpkin" and gas tank, one hose going to it and a 2 wire connector. If your tank is not venting properly it will not pass the EVAP selftest which is part of the onboard OBDII testing your vehicle automatically does. When your fill up with fuel or open your gas cap and hear a "whoose" of air that means there is a vacuum in the tank and air is rushing in. But it could be other things in the system including all hoses and fuel tank pressure sensor or the purges solenoid on the intake manifold, but if you get the air inrush when removing gas cap it could be vent solenoid or clogged vent line.

herkyhawki · #7 02-28-2006, 01:03 PM

Most troubleshooting leads to more questions before the answer pops up. When an OBD code points to any component, there always remains the question.. Is the component itself being bad, or if the sensor that monitors the component is bad?
What is the interface between the canister and the ECM?? What is leading the ECM to drop code on the canister? Is there a pressure switch or vacuum switch in this system that is monitoring the canister? If so, then you need to find out if the switch or sensor is bad, or if the canister itself is bad.

QuestAvMan · #8 02-28-2006, 01:26 PM

Well, I am still confused as I am not the brightest car guy in the world...But all I know is that I just got 50 Miles on a half a tank of gas...Something is not good at all....Something has gone real bad....I use to get great mileage for the longest time, it definitely has changed...

Thanks again
John

blazee · #9 02-28-2006, 03:02 PM

You said that he cleared the code.... has the light came back on? If the light hasn't came on again, you don't need to do anything.

BlazerLT · #10 02-28-2006, 03:31 PM

From my own experience, my problems with the canister only came about when I overfilled the tank and fuel got into the Canister vent line which is just a couple inches down the fill pipe from the top.

You overfill, you get fuel in there which will cause some wacky things until the fuel is gone.

Moral of the story, only fill your tank on the low setting and top it up to the nearest dollar after it has clicked off.

scholzee · #11 02-28-2006, 04:29 PM

Clearing the code and having no light for 50 miles can be deciving. The EVAP system will not perform the test until certian conditions are met. The gas tank must not be above 1/2 full , engine at normal operating temp and some other stuff, The test on mine only seemed to run when I was on the highway in the 45 to 65 mph range. ODBII actually gives date time and operating conditions when the test was performed.

ChazLynnwood · #12 06-19-2008, 08:32 PM

I must have a rare problem with my check engine light coming on. I was dagnosed by a poular tuneup chain with a bad gas cap,the code was cleared and the problem went away after replacing the cap. But 5,000 miles down the road the light came back on,When this happens I would remove the cap and reclose it ,and after 50 miles or so the check engine light would clear itself. This issue would come and go for the next 15,000 miles.. I went in for a full tune up when the check engine light stayed on constantly, and I was diagnosed with a clogged evap cannister at this time. I drive a 96 Blazer 4.3L 4door. Can some one out there give me a tip on how to fix this?I would like to pass an emissions test in 2010 when it is due for in Washington State..

BlazerLT · #13 06-19-2008, 09:48 PM

Quote:

Originally Posted by ChazLynnwood

I must have a rare problem with my check engine light coming on. I was dagnosed by a poular tuneup chain with a bad gas cap,the code was cleared and the problem went away after replacing the cap. But 5,000 miles down the road the light came back on,When this happens I would remove the cap and reclose it ,and after 50 miles or so the check engine light would clear itself. This issue would come and go for the next 15,000 miles.. I went in for a full tune up when the check engine light stayed on constantly, and I was diagnosed with a clogged evap cannister at this time. I drive a 96 Blazer 4.3L 4door. Can some one out there give me a tip on how to fix this?I would like to pass an emissions test in 2010 when it is due for in Washington State..

it is because you are overfilling the tank and filling the canister with gas seeing the vent for the canister is at the top of the fuel tank neck.

Get under your truck and remove the hose to the canister and allow the excess fuel to drain out of it and it will work again.

This is the prime reason why you don't overfill your tank.

ZL1power69 · #14 06-19-2008, 10:04 PM

Quote:

Originally Posted by ChazLynnwood

I must have a rare problem with my check engine light coming on. I was dagnosed by a poular tuneup chain with a bad gas cap,the code was cleared and the problem went away after replacing the cap. But 5,000 miles down the road the light came back on,When this happens I would remove the cap and reclose it ,and after 50 miles or so the check engine light would clear itself. This issue would come and go for the next 15,000 miles.. I went in for a full tune up when the check engine light stayed on constantly, and I was diagnosed with a clogged evap cannister at this time. I drive a 96 Blazer 4.3L 4door. Can some one out there give me a tip on how to fix this?I would like to pass an emissions test in 2010 when it is due for in Washington State..

Welcome to the site. Like BlazerLT said, if you overfill the gas tank, fuel gets into the evap system and causes issues. Dissconect the line to the canister and allow the fuel to drain out of the canister. The excess fuel will eventually clear out of the evap system and the computer should clear the code on its own. BTW, this thread is over two years old. Please refrain from posting in older threads.

POST REPLY TO THIS THREAD