exhaust smell from waste heat exhaust port

tillx7 wrote:

I called the dealer and the tech suggested blowing out the exhaust port, maybe wasps built a nest or spiders. Yuck. I don't think this would cause such a bad smell.

Any suggestions?

Yes.
Heed the advice of the professional.
At least do an inspection.

What you think likely is not right.

Combustion air has to come IN from some place too.
If that is obstructed, the flame will become too rich and inefficient and the exhaust will smell different.

And finally......this sometimes indicates that the insulation around the exhaust pipe has failed.....or the pipe itself has rusted through and you are getting hot gasses inside the wall and are on the verge of a house fire.

THIS COULD BE A DANGEROUS SITUATION that you should solve before there is a disaster.