Smell cabin Engine/exhaust smell in cabin. two different garages have said no exhaust leak. Your clothes and yourself smell like a weed trimmer

A modern, well maintained vehicle's exhaust is virtually orderless once the catalytic converter has fired up. What you could smelling is oil leaking from the engine, for instance, from the valve cover that then drips down onto the hot exhaust where it vaporizes. That oil vapor is then ingesting into the passenger compartment through the fresh air intakes. Try airing out the cabin and then set the ventilation controls to recirculation mode to see if the problem persists. Also, the oil vapor will only happen when the exhaust is hot. So if you don't smell it when you first start the engine, that could be confirming this cause. Look at your engine and see if you see oil and dirt oozing from the valve cover gasket. You can try to tighten the oil cover fasterners to see if it stops the leak, but the best approach would be to replace the valve cover gasket.