Charcoal Canister Replacement Option (4 Viewers)

[LostAfrican]

Our's is an 01, LX, with the charcoal canister in the engine bay (not in the back above the spare). This mod is definitely more applicable to those model years with charcoal canister in the front, though it could easily be adapted for the later years with the canister in the rear.

I have an aux fuel tank in our hundy - and its a gravity fed aux tank from Front Runner. It sits in the area above the spare tire hoist. Because of this, it is very easy to flood the charcoal canister since the new "full level" of the gas tank is above the outlet from the stock gas tank to the charcoal canister. Any downhill angle and fuel can flow from the tank right into the canister. So mine has been flooded several times. Also it was not allowing the tanks to vent so I had a bad fuel pressure problem - bad as in vapor and fuel spewing from the filler cap when opened after altitude changes

I found this canister on Amazon for $60 and used it instead of the OEM one ($600). The AC Delco one only has three connections, while the Toyota one has 4. The difference is that Toyota uses a clean air intake (from the intake plenum, after the air filter) vs. the AC Delco which uses the same outlet for fresh air and venting. Toyota separates the intake from the vent.

Mounting was super easy using some fat AC duct zip-ties and the original metal cradle. The OEM canister slides into this cradle, and there is metal spring tab you have to lever out of the way to allow the canister to slide up. There's a single bolt on the right of the picture below that needs to be removed too.

 

[LostAfrican]

Here's the AC Delco installed.

Now, the plumbing....
This pic from the 2001 FSM is helpful to know how the OEM system works and which lines to connect to the AC Delco.

The Air Inlet line is the one we delete with the 3 terminal AC Delco Canister. Everything else is the same...
OEM Purge Line goes to the AC Delco Purge Tube
OEM EVAP Line goes to the AC Delco Tank Tube (I moved this line to the top of the filler tube vent line on my setup with the aux tank)
OEM Air Drain Hose goes to the AC Delco Air Tube (Fresh Air Inlet). Remember the OEM has a separate in and an out here. The in comes from the intake plenum (filtered) and the out goes down into the drivers side frame rail under the battery. Don't connect the AC Delco Air Tube to your Intake Plenum...you don't want gas and fumes mixing in with the intake air, uncontrolled.

I plugged the hole in the intake plenum with a rubber brake bleeder zerk cover:

Here is the intakel line removed that ran across the top of the air manifold at the back:

 

[LostAfrican]

During my debug and testing on this I drove around for a while with the OEM charcoal canister, completely bypassed. I connected EVAP line to the drain hose into the frame rail (after I moved the EVAP port from the top of the OEM tank to the top of the filler neck breather. I noticed that my fuel tank was not pressurized all the time and venting every time I opened the cap. I also noticed smoother idles in D and a faster rev'ing and accelerating engine. I am not sure how the pressurized fuel system affects the fuel pump/injectors/idle etc, but the engine was definitely happier under idle or acceleration load. I do know that there is a return line from the injector rails to the tank. I did pick up a P0450 pending code with my ultra gauge - but this is to be expected with a freely venting tank.

Once I put the AC Delco in, I did not notice a change in the engine rev'ing/idling, compared to the improvements with the OEM canister bypassed - so that was good news. I cleared the codes and drove for a week or two and picked up the P0450 code again. To solve this I took the EVAP sensor off the metal bracket on the OEM canister and plugged it back into the harness and put a little hose on it and just tucked it in the engine bay. The hose doesn't go anywhere, so the sensor is reading the ambient air pressure. The hose is there to keep the sensor clean. I cleared the codes again and have been driving for a couple of weeks without any additional codes. So I think I have solved the code issue. I suspect that as long as the sensor is connected and the air pressure is close to normal air pressures the ECU will be happy.

Back to the OEM canister... A bunch of the 80's crowd (the cruisers, not the Duran Duran people) got into refilling their canisters. I opened the hundy canister by cutting the base off at the seam on the bottom. I believe it is glued or melted shut during manufacturing. I did manage to melt it in a few places with my dremel cutting wheel...but it came off just fine. Here are some pics of that. I do plan to refill it with fish tank filter activated carbon (it takes a lot BTW, in two separate chambers). I am working on a way to reseal it and make it serviceable. I think some kind of fuel proof RTV with a metal band clamp or clips on the bottom. The AC Delco one is quite a bit smaller and simpler, so it probably wont last as long...but at 1/10th of the price, its now in the "replaceable" category. In some markets Toyota does install a simpler one...so perhaps this has a lot to do with states where things are known to cause cancer and where they require more expensive solutions.... See this excellent thread and pics from @hoser. This thread made me a lot more confident about using a different canister and doing some re-plumbing.

Pics of the dissected hundy canister:

 

[Stralen]

Hello,

Thanks for this post on the 100 series charcoal canister rebuild!

Did you ever complete the rebuild? What did you use to seal the canister. Do you remember how much carbon it took to refill it?

Thanks!
Stralen

 

[Stralen]

Hello,

Thanks for this post on the 100 series charcoal canister rebuild!

Did you ever complete the rebuild? What did you use to seal the canister. Do you remember how much carbon it took to refill it?

Thanks!
Stralen

Completed my canister rebuild, thanks to LostAfrican for the pointers.

I had some of the same symptoms noted elsewhere, such as very high air pressure in the tank, and sometimes I could not fill the tank without tripping the gas pump. No ECU codes, though.

It took One of these, 5.5lbs:
https://www.amazon.com/Premium-Activated-Carbon-Aquarium-Charcoal/dp/B07577HN4N/

It was a little extra than the eBay cheap stuff, but because it was grains, I figure it packs more carbon per sqin than the cylindrical aquarium stuff, and I would like this to last another 200k.


And JBWeld KwikWeld
https://www.amazon.com/J-B-Weld-8276-KwikWeld-Reinforced/dp/B0006O1ICY/

To open I used a metal handled razor blade and a hammer and worked slowly around the bottom seam. The old carbon was small pellets.

I noticed that the lines for the largest hose on the canister has an odd 'alcohol' like smell, to me, and had rust. that lines goes to some sort of valve. I cleaned it with a anti-rust lubricant and starter fluid. Lots of rust came out, but got it all cleaned up.

In my case the existing filters inside were in great condition, so I reused them.

Afterwards, I refilled it and put it together. After ~500 miles, no codes, lower idles, AND No More Pressure in the tank! It seems to stick around ambient air pressure now.

I'm happy.

Thanks everyone for sharing your experiences on this. It saved me hundreds of $$$. All said on done, it costs <$38. So I have a full OEM part for less than the generic AutoZone canister.

 

[PabloCruise]

During my debug and testing on this I drove around for a while with the OEM charcoal canister, completely bypassed. I connected EVAP line to the drain hose into the frame rail (after I moved the EVAP port from the top of the OEM tank to the top of the filler neck breather. I noticed that my fuel tank was not pressurized all the time and venting every time I opened the cap. I also noticed smoother idles in D and a faster rev'ing and accelerating engine. I am not sure how the pressurized fuel system affects the fuel pump/injectors/idle etc, but the engine was definitely happier under idle or acceleration load. I do know that there is a return line from the injector rails to the tank. I did pick up a P0450 pending code with my ultra gauge - but this is to be expected with a freely venting tank.

Once I put the AC Delco in, I did not notice a change in the engine rev'ing/idling, compared to the improvements with the OEM canister bypassed - so that was good news. I cleared the codes and drove for a week or two and picked up the P0450 code again. To solve this I took the EVAP sensor off the metal bracket on the OEM canister and plugged it back into the harness and put a little hose on it and just tucked it in the engine bay. The hose doesn't go anywhere, so the sensor is reading the ambient air pressure. The hose is there to keep the sensor clean. I cleared the codes again and have been driving for a couple of weeks without any additional codes. So I think I have solved the code issue. I suspect that as long as the sensor is connected and the air pressure is close to normal air pressures the ECU will be happy.


View attachment 1525891

Back to the OEM canister... A bunch of the 80's crowd (the cruisers, not the Duran Duran people) got into refilling their canisters. I opened the hundy canister by cutting the base off at the seam on the bottom. I believe it is glued or melted shut during manufacturing. I did manage to melt it in a few places with my dremel cutting wheel...but it came off just fine. Here are some pics of that. I do plan to refill it with fish tank filter activated carbon (it takes a lot BTW, in two separate chambers). I am working on a way to reseal it and make it serviceable. I think some kind of fuel proof RTV with a metal band clamp or clips on the bottom. The AC Delco one is quite a bit smaller and simpler, so it probably wont last as long...but at 1/10th of the price, its now in the "replaceable" category. In some markets Toyota does install a simpler one...so perhaps this has a lot to do with states where things are known to cause cancer and where they require more expensive solutions.... See this excellent thread and pics from @hoser. This thread made me a lot more confident about using a different canister and doing some re-plumbing.

Pics of the dissected hundy canister:
View attachment 1525896

View attachment 1525894

View attachment 1525895

View attachment 1525897

Pretty cool! Could you see evidence that the charcoal had been wet with fuel or otherwise destroyed?

 

[LostAfrican]

Pretty cool! Could you see evidence that the charcoal had been wet with fuel or otherwise destroyed?

I couldn't tell a difference by just looking at the charcoal. My understanding is that the charcoal works by using its massive surface area (its very porous) and the fact that its carbon to bind with stuff that travels through it. Its like a big sponge. Its purpose is to absorb the ordor when the evap system is venting. If the only problem was the damage to the carbon itself (getting gummed up with too many impurities) we'd be ok, because the system would still vent. The issue is that the vent passage gets blocked, either by liquid fuel, or the valves getting stuck/blocked.

 

[PabloCruise]

I couldn't tell a difference by just looking at the charcoal. My understanding is that the charcoal works by using its massive surface area (its very porous) and the fact that its carbon to bind with stuff that travels through it. Its like a big sponge. Its purpose is to absorb the ordor when the evap system is venting. If the only problem was the damage to the carbon itself (getting gummed up with too many impurities) we'd be ok, because the system would still vent. The issue is that the vent passage gets blocked, either by liquid fuel, or the valves getting stuck/blocked.

That makes sense to me, as long as vapors can pass through the media, the tank should still be able to vent into the can. Unless the valves are not functioning...

 

[Stralen]

My experience was the same as LostAfrican's, the old charcoal looked ok. None of it was broken down or powdery. There were no liquids in the canister. Only a strong odor. The old carbon pellets seemed hard like rocks.

However, I did notice something else. After the rebuild I had to reapply the JBWeld to fix a leak. During the second disassembly I noticed that the rusty old fuel present in the lines had gotten into the canister. The rust had not been present in the old carbon during the first rebuild, only the valves which I cleaned up. Now, there was a very small rusty clump in the new carbon at the bottom of the canister.

I suppose that the canister pre-rebuild was clogged, stopping up the system, causing rusty fuel to back up. Now, its clear that things are flowing into and out of the canister.

Since the rebuild, it still seems to be running MUCH better. No more pressurized tank, no codes, runs smooth at 212k. I ran another fuel system cleaner for good measure.

 

[PabloCruise]

My experience was the same as LostAfrican's, the old charcoal looked ok. None of it was broken down or powdery. There were no liquids in the canister. Only a strong odor. The old carbon pellets seemed hard like rocks.

However, I did notice something else. After the rebuild I had to reapply the JBWeld to fix a leak. During the second disassembly I noticed that the rusty old fuel present in the lines had gotten into the canister. The rust had not been present in the old carbon during the first rebuild, only the valves which I cleaned up. Now, there was a very small rusty clump in the new carbon at the bottom of the canister.

I suppose that the canister pre-rebuild was clogged, stopping up the system, causing rusty fuel to back up. Now, its clear that things are flowing into and out of the canister.

Since the rebuild, it still seems to be running MUCH better. No more pressurized tank, no codes, runs smooth at 212k. I ran another fuel system cleaner for good measure.

Good report, thank you!

 

[Stralen]

Quick update:

This was the second time the JB Weld developed hair line cracks resulting in leaks of the EVAP system. It did throw a litany of codes, but what I found most interesting was how bad it affected engine idle and low RPM performance. Hairline cracks in the canister! During idle, the engine would cycle between an idle too low and bounce back up to stay alive. At low RPM at highway speeds (say down a hill), the engine would just barely try to stall, giving a little jerk on the truck.

This time I tried some zip ties and a Permatex Ultra Black to hold it all together. I did it right over the JB Weld, since it only had small cracks. Immediately, no idle problems, it runs great, and solid low end power. Hopefully it will last. Lots of trouble to learn to fix this and save a few bucks!

https://www.amazon.com/Permatex-85144-Right-Stuff-Gasket/dp/B000HBNU4U/

 

[mmbirtcher]

Looks like a headache. I’ve been interested in the Frontrunner spare tank but have an ‘04 LX. Based on the location of the Frontrunner tank, do you think my canister would prohibit install? I wonder if I can delete the canister and fool the sensor. Kind of like my son deleted the catalytic converters and tricked the sensors on his GTO. Thanks.

And where did you source the Frontrunner tank?

 

[Stralen]

It's really not hard to get to. I've been under there so many times I can do the whole thing in a matter of minutes. Even rebuilding the canister is not hard. Just time, trial, and error.

As for removing it... My concern would not only be the sensor (which will turn off VSC if there is a code), but the effect on the vacuum system and performance. When the system was stopped up before I repaired the canister, it idled a little higher, and sucked a tad more fuel. After, when it leaked, it idled lower, and tried to stall.

During the last several months while the canister is fixed, everything runs like a champ. I even went on a trip to NY from Central USA and it ran awesome the whole way there and back. Passed easy, even darted through Brooklyn traffic for a week. It's not like when I first got it- it felt like it was always too heavy, lacked power. Granted, I've done other repairs since I got it, but now I can even get *16-18 miles per gallon* when at first I struggled to get 8-12 MPG, and better low end power as something extra.

So, I'm sure it would run if you removed it, but after everything I've been through, I feel it runs better with EVAP working properly. Maybe it could just be relocated.

 

[Vikingsbeard]

Awesome stuff! Last week it was in the high 90s here in SLC and I had some stalling and gas smell come from the hood. The Vapor Canister was going crazy, so looks I need to do this.

I was wondering if there is any filter material I need / should replace while I changed out the activated carbon and if anyone had any pictures of said filter material, and or description of it.

 

[Pyrenees]

@LostAfrican I have a question. Did you run the Delco canister + the vented valve/sensor for a while without codes? You also rebuilt the OEM one so I wasn't sure if the delco modification was successful of not. I've got a recurring P0441 (just that, no other codes) for "evap emission purge flow fault". I replaced the gas cap with OEM toyota and reset the CEL but it came back two months later.

 

[LostAfrican]

@Pyrenees. Yes I am still running the Delco canister actually. Code free. I did have to replace a cracked vacuum line between the crank case and the canister to get truly code free though. I have passed emissions since I did that mod (in AZ). I haven't refilled the original canister yet, because I don't need to and I am still trying to figure out a way to make it easily re-openable so I can refill it often if needed. RTV and some band type pipe clamps seem the most plausible. I worry that the RTV is not good with gasoline tho.

hope that helps! (sorry for the delay, took me a while to spy the alert).

 

[gatormark91]

@Pyrenees. Yes I am still running the Delco canister actually. Code free. I did have to replace a cracked vacuum line between the crank case and the canister to get truly code free though. I have passed emissions since I did that mod (in AZ). I haven't refilled the original canister yet, because I don't need to and I am still trying to figure out a way to make it easily re-openable so I can refill it often if needed. RTV and some band type pipe clamps seem the most plausible. I worry that the RTV is not good with gasoline tho.

hope that helps! (sorry for the delay, took me a while to spy the alert).

So you just unplugged the purge VSV on the canister and left it unplugged? It didn't give you any codes doing that? I refilled my canister, but I think it's plugged internally, so it's done. I bought the VC-120 and what to do with the canister purge valve is the only question I've got. Thanks!

 

[Pyrenees]

I bought the VC-120

What's that?

 

[gatormark91]

What's that?

The AutoZone version of the GM canister above in this thread.

 

[Pyrenees]

Cool. Yeah interested to know as well about the VSV. I went over my vacuum lines on the canister and put little hose clamps on all of the junctions to tighten them up. Just in case it was leaking a bit. Tested the resistance on both VSVs and they were in-spec, at least when cold. We'll see if the code comes back. @LostAfrican I would also like to know what you did with the VSV on the delco canister. AFAIK this is the only thread I can find for a 100 series aftermarket canister, so you're pretty much a hero, haha.