alright, i did the piston lift pump install thinking my original style lift pump that wasnt even a year old was defueling at highr rpm's this weekend, i am stll averaging 10-11 mpg, with not much power. somethings not workin right.

 

How heavy is your foot?

 

um, in town i kinda get on it a lil but on the highway i stay at about65-70

 

On my red truck I had I was semi-aggressive in town and still got about 15-18mpg city. Check your air filter and make sure it is clogged. Also pull the intake tube and make sure nothing is in there, somebody posted a picture of a rat that had crawled into a intake tube and was blocking the turbo on a Dmax, highly doubt that is your problem but I would check to make sure nothing is blocking.

Could also be the fuel filter if it hasn't been changed.

 

Dose it smoke?
("congested" intake restriction or "constipated" Exhaust restriction = black smoke)

 

Yea it smokes when you start it, itl smoke a nice little puff off the line if your agressive with it, I checked the air filter earlier today it can ride for another couple months. My exhaust is stock, muffler delete. Fuel filter new, piston lift pump new. Timing bumped other than that its stock

 

well you should notice the smoke if you had a restriction,

"THE GUY WITH THE RAT SHOULD OF THAT THING HAD TO OF SMOKED LIKE A edit"

Check your lift pump?

 

If you have any leaks from your turbo to your intake, and your exhuast manifold to your turbo, you won't get that enough boost. Do you have a boost gauge? If not, put a plumber's cap over the exhaust and intake side of the turbo, one with a valve stem through it, use an air compressor to pump 40 psi of air through the motor. Use a spray bottle of soapy water to spray on fittings to check for leaks. I have done this to mine a few times. It works good.

 

Another thought, is your new pump timed correctly?

 

a fuel leak would cause poor mileage. check the little things to like, tire pressure, brakes dragging, hubs lock, air and fuel filter.

 

I had similar problems. Found the tv cable going to the tranny broke the spring on the throttle, Look and see it is still there. Also may need adjusting, refer to haynes or chiltons for correct adjustment. My truck was bogging down and losing power. The tranny was taking the engine down, and not transferring the power to the wheels. Cheap fix if this is it. The lift pump timing?................... I am wondering if this is even possible to mis-time? It should just ride on the cam. Only one way to pump fluid. I would think the timing would be important on the fuel pump. But I have been and will continue to be wrong.

 

Oh, I thought you put in an injection pump. Nevermind.