My diesel is doing getting a low fuel economy, should I add an additive?

I just got a diesel 2018 Honda Civic with just 4500 miles on it. I'm only getting 39mpg. Should I put a fuel additive in?

Asked on 16 June 2020 by Campbell f

Answered by Dan Powell
That's very low mileage for a diesel. The mpg is most-likely caused by extra fuel being injected to force the DPF into an active regeneration. The car needs more miles, not a fuel additive.

For more information on DPFs, see:
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