exhaust smell finally resolved!!!
 

Just thought I'd thank everyone for their help with my stinky z, and to let you know what the end result is.

yep, it was coming through the back hatch. But there are some other seals around that make a difference also. there are two round gromets, (I think they are gromets anyway) on the top part of the hatch twards the edge. thery were cracked and brittle, but I didn't think they had much use, except for cushing while closing the hatch. But they do have something to do with the fumes. Also there is a piece of vinyl on the top inside part of the hatch, sortof like upolstry. I didn't think it was anything except for looks, but nope, there is a seal around or under that thing too!

I decided finally to take it to a real shop where there are at least 6 z cars there at all times!! (my mom had been telling me I should take it there for along time, but I thought my mechanic was the best!) anyhow I decided to take the car where it belongs... with her brothers and sisters! This mechanic found and sealed up everything within 1/2 a day. I have not piced up the car yet, but I drove it yesterday and smelled nothing!!! both windows down! i'm soooo happy! I can't wait to have my car back! it's only going to cost about $130.00 too! so, now if anyone asks about this problem, those 2little round guys do serve a perpose! I can tell exactly what is being sealed up next week.

Also the car is not a California car! I thought for sure it was, but it does not have a catalic converter.

well, it's not just those round gromets... but they matter!

thats good to hear!

Yes please do tell us everything that the shop sealed! I have the same smell issues.

I will! I hope to get my car back today or tomorrow. I can attach some pictures too.

Other rear seals to replace
 

I had the same issue with 71 240Z. Here is a list of seals that were replaced on mine to get rid of the smell along with some other things:

Full hatch seal
Round hatch grommets
Lower Inerior hatch panel
Sealed up brake light interior cover
Seals around brake lights
Seals around tail light panel
Sealed up area around license plate
Seals around interior qtr panels

Other things replaced:
Gas filler neck
Return fuel lines
Exhaust muffler

Your car may not need all the things that my car needed. Considering that most of these cars are thirysomething years old, not a bad idea to replace all if you are uncertain of the maintenance and condition of these various parts.

All of this work was done at the Z Car Garage in San Jose (Just in case you live in or around the area check them out. All they do is Z cars.).