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Techron & Mercedes diesel--kosher or what?

I decided to try Techron in our '93 Mercedes 300 D[iesel]. Web posts said it couldn’t hurt.

So on a couple of hundred or so mile trip today the car lost power intermittently. The engine ran fitfully–like it was starved for fuel, blowing black smoke. And then it ran fine until the next time the death rattle set in.

When I bought the car it had 3 of 5 glow plugs bad. After replacing these, the car would blow black smoke on hard acceleration, but this cleared up.

So, is this just accumulated gunk in the fueling system…or what?



Techron is a gasoline engine detergent additive. Not a diesel engine detergent additive. Keep filling the tank with pure diesel fuel and hope nothing in the fuel system was damaged.


Nothing in the fuel system of a 1993 Mercedes Diesel will be damaged by Techron. Mercedes only started recommending Diesel Techron when they changed the fuel system from indirect to direct around 2001. Prior to 2001 you’re good to go.

Techron can indeed loosen up some accumulated “crud”. I always recommend changing the oil and diesel fuel filters after a dose.

Thanks for the replies. I ran the full tank of Techron-treated diesel and filled with fresh fuel last night. Tomorrow I’ll change the oil, oil filter and the two fuel filters. I am thinking that the “crud” may have clogged the fuel filters and causing the intermittent fuel starvation.