I need your input fellow BOGs. I have a 9-year old Nissan pick-up which recently failed a smoke emission test conducted by the LTO. This go-anywhere pick-up has been stone reliable for me and would hate to sell it anytime soon. I exclusively use Shell oil and Diesoline exclusively for 5 plus years already. The smoke emitted is white when revved up, though the amount of smoke seems a bit excessive. Is there a service entity or a product out there I can use to solve this? Thanks for your help!