KNBC undercover cameras caught local JiffyLubes and EZ-Lubes upselling customers to buy engine-flushing and fuel-injection cleaning services, services which have been forbidden by auto-manufacturers because they’re unnecessary and can severely damage your engine. One guy’s engine died while he was driving on the highway, and it cost him $5,000 to replace his engine.

Engine-flushing is supposed to clean out the gunk and deposits in your engine, but breaking these up is like dislodging a blood clot – they can jam up other sensitive components. Honda calls fuel-injection cleaning an “improper repair procedure” as it can damage other injection parts. They and other makers have sent notices to repair shops telling them not to perform them. Despite this, KNBC received complaints from across the country from consumers with cars damaged after getting upsold into the potentially dangerous service. See more in their video report, below:In a statement, both JiffyLube and EZLube say it wasn’t acceptable for employees to lie and say services were recommended by the manufacturer when they weren’t, and the employees caught would be fired.Could This Damage Your Car? [KNBC]

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