Is there a dye available that can be introduced into the throttle body to identify exhaust leaks? For instance, something similar to the compressed air can with a straw used for seafoam?

 

Not really. People use smoke machines to find vacuum leaks, I assume it would Be good for exhaust leaks too.

 

Here's something you could try if you don't have a smoke machine.... shop vac and windex. I've never had to resort to something like this because my exhaust leaks were always really obvious and I could find them by ear or by feeling for the exhaust with my hand at cold start.

 

Smoke testing the exhaust is definitely the industry standard for finding exhaust leaks. Takes about 10 minutes, will find ANY exhaust leak.

 

The problem I have I live in apartment and I can't work on my car in the parking lot. I have to work on the street. I own a Shop-Vac, but unfortunately, there's no power source out in the street.

I'm unable to raise my car to a height enough to inspect the upper portion of my exhaust headers. This is why I would like to use smoke through my throttle body.

Does anybody know someone in the San Jose - Sunnyvale, California area who would let me work on my G35?

 

You can actually see a lot just by using a bigger inspection mirror and a good flashlight. I'm fairly confident I could ACCURATELY smoke test my coupe with it sitting in the parking lot if I had to. Everything exhaust under the car is very accessible, headers you could inspect from the engine bay.

Just make sure you do it on a calm day, no wind whatsoever. No need to bust out a Kestrel, if you can feel wind or see any plants waving around it's too windy for accurate smoke testing. Lighting a wooden match is a good way to test wind as well since you can watch the smoke coming off of it, if there's enough wind to disperse the smoke from a wooden match then you will probably have a hard time finding it leaking from the exhaust.