Can one bad injector be causing this 3 to 3.5 MPG?

How long have the truck been sitting could be build up on the injector that cause it to throw a fault code also trash in fuel could do it but if it is the injector it would be a lot cheaper to replace all six injectors and cups at one time because just having one replaced now and six months later having another replaced will cost you more. The labor cost to pull the head will run you around $2000 one injector and cup around $1800 while you can get a complete injector and cup set for around $2886 these prices are for the D16 I just had all six replaced

 

Just curios how they diagnosed a bad injector? Did they take the Rocker Cover off? I have seen a Volvo throw a electrical fault for a injector, turned out it was a cracked cylinder liner. Allot of Volvo dealers use PTT and don't do any actual hands on.

 

I agree, if you do in fact have a bad injector replace all six with a matched set. I don't think I would ever just replace one, even if the others didn't have alot of miles I would still do all six.

 

Pull one of the plug wires off your car and see what happens to the gas mileage.

 

i would replace all 6 because of the cost factor
replacing one instead of 6 because the others will soon follow isnt a good reason
they all fail at different rates on the boats we never replaced but just a bad one
2 years later maybe another one but boat engine rooms and boat mechanics
dont have dealer prices

 

I don't know about Detroit but a cat injector is like 550.00 so 3300.00 for six ! Plus labor ! I would and have done just one and will do it again !

 

Doing them all at once means you only pay the labor once. Do them as they fail means you spent that labor 6 times, to each their own though.

 

Holy crap. What dealer screwed you? $1000 labor is 9-10 hrs which is rediculous for 1 injector.