with 200,000 miles on the stock charcoal canister and probably the stock EGR (it hasn't been replaced in atleast the past 3 years) do these need to be replaced? also, is there anyway the EGR could be causing bad gas milage without setting a code? wut about a charcoal canister? does it require and mantence?

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- David
88' GTA 5.7L TPI MODS---> air foil, K&N, Shift Kit, 180* therm, TB bypass, Gutted CAT, Flowmaster 80 Series Muffler added to Unkown CatBack, Ported Intake

http://www.geocities.com/david_angel_16

 

hell i've wondered about the canister as well. does it ever need replacing? does anyone know? if so at what intervals?

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86',88',89' IROC-Z, 350 TPI, 700-R4

94' Formula, LT1, 6spd

 

i *THINK* all it does is absorb gas fumes from the ?tank?

 

EGR's get clogged up with... exhaust carbon (what a concept) and need to be cleaned or replaced depending on how bad the engine is building up carbon in the EGR. It varies so widely depending on the condition I would be afraid to stick a number on it, but if the EGR got clogged in 100k miles I'd be more worried about the engine than the EGR.

The canister has a filter on the bottom, its like a thin, round, flimsy fiber thing and is supposed to be replaced every 20,000 miles or something like that. Its not going to affect mileage, but a bad or sticking EGR can. And I wouldnt trust the ecm to set a code for the EGR, its supposed to but it doesnt have a very good way of determining that anything is really wrong.