After first noticing this problem, I searched around and found my flame trap popped apart with the bottom hose piece cracked/stretched out. I replaced the flame trap, holder and lower hose piece. For a while, the smell seemed to go away. An obvious problem with an obvious "fix", no?

But the smell is back. With the car just sitting on the driveway, if I start the car and step outside I smell it. Seems I can smell it inside the engine compartment. I can, of course, smell some at the tailpipe - but I expect that.

I have done all sorts of testing, searching all around this beast. No fluid leaking under the car, no obvious cracks/holes/gaps in the exhaust line, all hoses appear ok and connected under the hood. I have sprayed water over the intake components seeking leaks impacting idle and find none. I tested O2 sensor voltages (both the green wire and black), test grounding and applying voltage to the green O2 wire and got the expected results, checked AMM voltage at no and increasing RPM, even adjusted the AMM a little more lean. Nothing seems to affect this. I checked the fuel filler cap, fuel overflow line, sought smell inside the trunk, etc. Nothing that I can find.

It does seem that the smell is most pronounced upon starting the engine and that, with more run time, it gets less obnoxious. But I just cannot seem to find the source/cause.

So I am stumped and wondering if anyone here can help. Thanks in advance!