I've barely driven my Z lately, due to the continous crap weather going on, but I've moved it out of the garage and back in a few times. Did an oil change, etc. Anyway it seems like the exhaust has a more potent smell than I remember. I hope it's not just my Z31 injectors crapping out on me. Anyway I do have a vaccum leak going to the charcoal canister, the line is pretty much torn through, it got wedged behind a pulley and the pulley cut through it. My question is, would that vaccum leak cause a more potent smell or am I just coming up with reasons to avoid something worse.

 

Might just be an exhaust leak. The cold weather can do that until the exhaust warms up. Or the cold weather could just be causing a really rich mixture which will also cause a stronger exhaust smell.

 

cold weather can cause an exhaust leak? That's true too, I didn't think about it running a bit richer when it hasn't started in a while or been colder, but will the the vaccum leak cause anything?

 

Metal contracts when it's cold. As the exhaust warms up the metal will expand and seal any small gaps. It would be short term leak that would go away once the metal has heated sufficiently. Yes a vacuum leak can mess with your mixture. But it would generally only be at idle. If that line is torn and the canister is not allowed to evacuate its stored vapor to the intake manifold then it could just be venting to the atmosphere. Are you sure it's not fuel vapor mixed with exhaust that you're smelling?

I personally think it's just the cold weather and the fact that the car has been sitting thats causing your odor. If you suspect a problem though you should definitely investigate though cause it's better to be safe than sorry.

 

Bah, it could be one of my injectors is leaking a spec. It looks a little wet around the one injector. I had the car on, and was revving it a bit. It didn't look like it got anymore wet or anything around the injector, but it may be the very start of a leak? I guess I'll just fix that vaccum line, and keep an eye on the injector. I wouldn't be surprised if it's one of the 280ZX injectors I reused.