i'm getting 13 mpg. not too good. now, mostly i do city driving with some freeway and some highway for work. about 200-250 miles a week or so. when i first got the car i would get about 19-21 for the same type of driving.

background info: 199950 miles on it. my fuel gauge does not work, nor does my DIC. Either the bulb is out or the unit does not work anymore. I have a can tune from ZZP and a 3.4 pulley and u bend delete with a cat and running al104 plugs. these have been on the car for between 1.5 years and 2 years. I put them on about a month or so after getting the car so there is history there.

i know im getting 13 mpg by setting the trip when i get gas to zero, then running the car nearly out of gas either on purpose or accident and then dividing the mileage by the gallons i put in. for the record, its a 16 gallon tank but it will take 18 gallons if run dry. i put 17 in it semi regularly.

i have no check engine light on the dash nor do any codes show up on torque pro scan with the android app.

now, when i go up a hill the car wants to kind of, i don't know how to write it, spudder or something, like its having a hard time. the rpms dance, like 1000-1500 if you try to go at a steady pace (like 45 mph) up a hill. but if you accelerate it accelerates as normal.

i would say the performance is down but the boost still works.

checked vacuum lines, look all good and connected. i replaced them a year or so ago. the plugs n wires i replaced about the same time.

things that make a small difference that i will put out up front: i warm the car up in the morning for 5-10 minutes when its cold (so i can sit in it). sometimes i eat lunch in it and keep it running when its really cold out. and finally, the tire pressure may be a little low. these should not account for the huge drop in gas mileage though.

i have torque pro and can use it to observe whatever parameters it is capable of observing. having it idle in the driveway at operating temperature produced nothing crazy that i saw but i'm not really sure what i should be looking at and i need to take it for a drive and look but i need to know if i can find any clues by looking. i can see intake temperature, coolant temp, vacuum, boost, MAF, rpm, etc. maybe if i just know what normal parameters are i can check for them while driving.

i could run some seafoam in it but i don't think that's going to solve the issue. i'm thinking its gotta be a sensor or egr valve. its not behaving like the cars i've had in the past that needed a new egr valve, though. no gas leaks at the rail or injectors or anything like that.

i need to get this fixed asap and can't afford to just replace several sensors without knowing which one it is right now. i was hoping to make it to tax return and then do a lot of things at once but its not going to happen. anyone else ever have the same kind of symptoms?