Abstract: An apparatus for in situ testing an exhaust system of a conventional internal combustion engine safely, via electrical heater, generating smoke from a smoke-generating fluid contained within a chamber, and then communicating such smoke through the tailpipe components comprising conventional exhaust systems such as tailpipes, clamps, gaskets, hangers, welds, and flanges. By observing smoke emanating from any of the plurality of pipes and associated connections in an exhaust system, any and all leaks therein may be identified and precisely located. The apparatus includes a tapered preferably frustoconically-shaped play which is sealably received into the tailpipe of a vehicle being tested for exhaust leaks.

Abstract: An apparatus for in situ testing of an internal combustion engine for vacuum leaks is provided. In accordance with the present invention, smoke is generated from a suitable smoke-generating fluid in chamber means, and then sealably communicated through conduit means to the intake manifold of a vacuum system in an internal combustion engine. By visibly observing smoke exiting from any of the hoses, flanges and gaskets contained within a vacuum system, leaks therein may be readily located.