hope that makes sense
since i converted to tpi from tbi i have found that no matter what the weather is like the tank pressurises ,i have all the connections on properly to the cannister ,when taking the car for a run it tends to make the idle very very crappy to the verge of stalling
IF i take the hose off of the cannister from the tank i have no hassles at all ,i need the cannister on for inspection
does the purge valve in a cannister ever die ???
shall i just stick a filter on the end of the line ???
thanks

 

i'd say it's time to replace the canister

 

you actually have to replace them ??????????

 

Aus,

What year is your RS? The EVAP canister design changed around 1987. Earlier canisters had a replaceable filter pad on the underside (or, would that be the top in your hemisphere?). Later canisters had no such filter, and atmospheric dirt can clog the carbon medium in the canister so that it does not vent.

There is also a tank pressure control valve at the canister, and of course the purge valve. The purge valve is replaceable, and I've seen them available at auto parts stores - they're fairly generic. I believe the tank pressure is controlled by the same purge device on the later design canisters, but I'm not positive.

One means of testing the canister is to remove it from its mounting and place a plastic bag over the bottom vent opening. If you apply a vacuum to the purge port, the bag should get slowly drawn into the opening.

Getting a bit warmer there lately? Tank pressure is fairly temperature dependent.

 

the RS is a 1991
car has only done 60 k miles thought the evap cannister would last longer than that
will do the plastic bag test tomorrow ,thanks for the advice
btw YES it is getting a bit on the warm side over here .......summer has a tendency to do that LOL