Boost leak??
 

Well just bought my truck couple weeks ago an i'm getting only 7-8 mpg or even less. Just checked my codes an got 0237 found out that thats for low boost pressure. Does that mean i have a boost leak? An also got a "P1693 Generic fault indicating a fault in the bus or PCM/ECM interface" i was messing round with my edge box under the hood do i jus need to get my truck reflashed. Could it be anything else beside boost leak? Thanks guys

could be a bad map sensor

Wow I thought my 12 mpgs sucked. I would bet it's a combination of things, I'd start with the boost leak check. Like Cowboy said it could be a map sensor. There is another sensor right behind the map that could also contribute if carbon has built up on it. Pull it and clean it with carb cleaner. You may want to also adjust your valves. It can make a difference. So many variables play into mpgs, especially weather. But if you are really getting 7-8 mpgs, my bet would be there is more than one problem.

clean the map and iat sensor. check turbo boots by the lower part of intercooler on drivers side they like to rub on fender and leak. get a better lift pump, check your air filter.

As stated above clean the sensors. Check for leaks at the boot they are prone to leak with age.Miles on the truck?

if you haven't checked valve lash yet i would mine was way out of funk and i was down to 14 mpg but i got them right again and now i get round 18. good luck! :tu: