1993 240SX KA24DE Charcoal Canister Prob's

[zest2live]

Originally posted on 240sx tech forum, but no takers there. Maybe this is a better place for my questions?

Searched "canister"....archived....63 returns....not the help I needed.Engine has been completely rebuilt, but failed smog. Had a lot of simultaneous sensor errors that were traced to the EFI Harness itself (after ECU swap w/same symptoms). Replaced the harness, but still failed smog, however, all sensors operating correctly now. Replaced cat. conv. and finally passed smog.

After all this, the engine still ran rough and lacked power. "Triple-checked" the timing (which had been "tweaked" for passing smog) and set the idle (tps off), but still lacking power. Checked the troulble shooting section of FSM for hesitation/lack of power. Because virtually everything is new (PCV, EGR, etc) I went to "Procedure 7" (EF & EC 68) and disconnected the purge line and plugged it.

The hesitation and lack of power were resolved by this.

However, while trying to disconnect the "baked on" purge line, I broke the nipple for the vapor line. I tried to buy a new canister from Nissan, but they tell me it's not made anymore and no one has any in stock.

Now to my question's.

1. Why and/or how can the canister system cause my engine to run so poorly????

From what I've read, the canister filters fuel vapors from the fuel tank and recycle's them into the intake manifold to be burned off. So how can this not working right cause my engine to run like crap....it just seems like an "extra". What's the vacuum line's role in all this? Is it there to operate a valve in the top of the canister when manifold vacuum reaches a certain level? What's coming through the purge line (and which way is it flowing) (I would think it's flowing from the canister to the intake manifold)? And why does plugging the purge line resolve the problem?

2. If I can't find another canister, what do I need to do to by-pass this system and what are the consequences to engine performance??? (I understand I may fail a visual smog inspection as well as fuel tank pressure test inspection).

3. Are other components of the smog system (EGR) inter-dependant on the canister system? In other words, can I just remove the canister system (per however that's properly accomplished) (and how would that be accomplished) and no other systems will be affected?

I know this is a lot of anal questions....but that's just how I roll (says old guy).

Thanks in advance for the help.