What is the percent rate to declare a good injector from a bad one ?

I am going to take mine to the dealer and have them tested but I want to know what to expect. My truck is getting very poor mileage lately, I tried all sort of remedies, and gained a little but I am down to 13mpg empty and 9mpg loaded at 60mph/65 mph

I do see a little smoke, and I don't "make oil", I am sure the injectors are the problem. I wish it was liike the 2nd gen, where you can buy new ones for 300 bucks total.....

 

I'm in the same boat. Getting more smoke and a white smoke at idle. Decided for what it cost at the dealer for diags and replacing just one injector with a rebuilt it's more cost effective just to replace all six with brand new Bosch injectors. I found a place that has new Bosch injectors for $335 each with a $150 core charge.

MikeyB