i was working on my truck recently and came across the evap purge canister.
not familar with it on my firebird.
what exactly is it and what does it do.

 

If your talking about the round canister in the rear wheelwell on the drivers side, its part of the emmisions system, EVAP. The engine purges the gas vapors out of the tank and burns them. The canister is filled with charcoal, and over time it breaks down and can get sucked into the system, which is a pain. i just replaced my whole system, the charcoal canister, the vacuume switch and purge sol cause charcoal got sucked through the lines.

 

You know this seams to be a common problem with camaros.
What if you put a clear fuel filter in line that way if it takes a crap it does not go into the engine?


Chris G.

 

how whould a clear one prevent it. do you mean you could see it before it get bad

 

Well what I mean is if it takes a dump on you you can see the carbon in the filter.
I would not want a bunch of carbon getting sucked into my engine.
Can't be a good thing.


Chris G.

 

It wouldnt make much sense to put a clear fuel filter in line to be able to see when the charcoal canister is bad. Thats just another part to replace when the canister goes bad and charcoal gets into the line. The charcoal wouldnt get into the engine anyhow. Once it gets to the vacuume switch and purge sol, it will clog them up, and then set the SES light, since normal EVAP operation would be inop. Then just follow normal servicing, replace the canister, which runs 57.00+- at the dealer, the purge switch, which runs25+-, and the purge sol which also runs 25+-. Take an air compressor and blow the remaining charcoal out of the lines from the vacuume switch to the end of the line where it hooks to the canister. Your looking at 110.00 and you have a new EVAP system. With all the emissions testing now-a-days, it makes sense.

 

Good point.
But if you put the filter right after the canister you won't have to clean the line.
Or replace the purge switch and the purge sol.
Just an Idea.
I like clean Air.
I like my cats.


Chris G.

 

True, It would eliminate charcoal getting into the line. But, Im wondering, it may cause a flow problem, with the system trying to suck the vapors through the fuel filter?? Besides, how often does the charcoal canister fail? But, a filter of some type could def. prevent charcoal from getting to the lines.

 

I agree on how would the vapours get through the filter. Seems pretty rare to me for these things to break down. In fact I've never heard of one breaking down even on high mileage cars.

Lots of people here on the board take them out of their F-bodies. Not sure why. Space savings? Anyways, they use zero horsepower, have no moving parts, and if you take them out you can lose up to 11% of your gas mileage. Screw that. I say leave them in.

 

My point. These systems are very reliable. I had to replace my EVAP system just about 2 months ago. My cars got 114,00 miles on it, and the only reason I had to replace the vaccume switch and purge sol is cause they got charcoal in them. If I would have been smart, I would have replaced the charcoal canister when i did the 100,000 mile servicing and everything would have kept on going. But, I tryed to scruntch money. It worked for 14,000 miles... .

 

Not only that, it's a fairly cheap fix and one of the easier things to change on these cars.

 

I see your point about the paper filter.
You could use a glass one with that mess screen filter in it.
I know that would not affect it's flow.
Like this one.
http://www.jcwhitney.com/webapp/wcs/...atalogId=10101



Chris G.

 

can a car run with out the canister

 

Yes, it will run, but it probably wont pass smog / emissions testing, depending on the status of the rest of the 6 smog items in OBDII. The whole point of the canister is to "soak" out the vapors and store them untill the sol purges the syatem and burns the excess vapors. Plus, as mentioned before, your gas millage will suffer. Thats the whole point of the syatem, to better emissions and gas milage. Its such an easy cheap proven system. If its broken, just fix it and move on. You can replace the whole system for 110.00, your self, in the driveway.

 

will i was wondering because i was doing a rebuild on my 99 sierra 1500 and broke the canister. before the rebuild the truck was cranking up but dieing imediately. i droped the tank and now replaced tank. and im icheing to give it a try but im still weary about not have the canister equiped. do you think it would still be safe to give a try.