only getting 9 mpg help

[jefff82]

i recently bought a 97 4 dr Tahoe 4wd for a family vehicle. wasn't really monitoring the mpg cause I know its not going to be much. decided to check today and was getting barley over 9. I was figuring in the 12-15 average. problem is the truck runs well. no cel starts right up. it has 168k had a new fuel pump put in before I bought it( have the receipts). changed oil and filter. cleaned maf and added a spectre filter when I got it. plugs were done at 100k. original owners kept all receipts. tires are at 44 psi and are 245 75 16. not sure if fuel filter was done with pump but I nned some advice to get some better mpg. any info would be great.

 

[white7wolf]

I would maybe take a look at the fuel filter. Honestly though I only get about 10, maybe 11 in town.
Others will probably chime in with more info but filter might help especially if the pump was just changed

 

[SunlitComet]

first off knock your pressure down to what is printed on the door jamb sticker. should be more like 36psi. if you are concerned about fuel pressure buy or borrow a tester from autozone to get your reading. how exactly are you measuring the consumption?

 

[jefff82]

I would maybe take a look at the fuel filter. Honestly though I only get about 10, maybe 11 in town.
Others will probably chime in with more info but filter might help especially if the pump was just changed

I looked at the receipts from the fuel pump install. No mention of fuel filter. Last time i can verify by receipts was at 70k

---------- Post added at 01:31 AM ---------- Previous post was at 01:23 AM ----------

first off knock your pressure down to what is printed on the door jamb sticker. should be more like 36psi. if you are concerned about fuel pressure buy or borrow a tester from autozone to get your reading. how exactly are you measuring the consumption?

Ill drop pressure down today. I read that around 44 is best for mpg. Not worried about pressure just looking to see if there's anything to get the mpg up a lil bit.i filled up and drove 85 miles and stopped by the gas station to get a drink filled up which was 9.1 gallons. 85/9.1
= 9.34 mpg

 

[ccapehartusarmyINF.(ret)]

if you know were to get ahold of a scan tool see if your still running in open loop
cuz 9 mpg is a little low the 97 3/4 ton my grandfather had with the 7.4 liter got almost 9 to 10 mpg except when he was towing a trailer then it was more like 7 mpg

 

[Rangel]

not sure what kind of tires your running, but 44psi is usually the MAX psi for a tire. unless its load range E. the door jamb sticker on my two NNBS's are 30psi and 32psi.

other than that. extremely easy pedal from a start. I strive to keep my rpm under 1500 at all time. 60mph max.

 

[SunlitComet]

44psi will eventually eat up the tires the wrong way. i use lt's load e 265-75-16 in front and 285/65/17 in the rear i keep them at 40psi cold pressure.

---------- Post added at 07:57 AM ---------- Previous post was at 07:56 AM ----------

if you know were to get ahold of a scan tool see if your still running in open loop
cuz 9 mpg is a little low the 97 3/4 ton my grandfather had with the 7.4 liter got almost 9 to 10 mpg except when he was towing a trailer then it was more like 7 mpg

it can happen in closed loop too.

---------- Post added at 08:21 AM ---------- Previous post was at 07:57 AM ----------

not sure what kind of tires your running, but 44psi is usually the MAX psi for a tire. unless its load range E. the door jamb sticker on my two NNBS's are 30psi and 32psi.

other than that. extremely easy pedal from a start. I strive to keep my rpm under 1500 at all time. 60mph max.

don't you ever come to california driving like that. you will piss off even the people driving hybrids and you don't want to piss us off. even highway tractors drive faster then that here.

 

[jefff82]

if you know were to get ahold of a scan tool see if your still running in open loop
cuz 9 mpg is a little low the 97 3/4 ton my grandfather had with the 7.4 liter got almost 9 to 10 mpg except when he was towing a trailer then it was more like 7 mpg

And mine is city driving only . only on a highway for a mile or 2. Mainly to run errands with my daughter. Not sure I want to take on a trip with that mpg

---------- Post added at 01:00 PM ---------- Previous post was at 12:56 PM ----------

not sure what kind of tires your running, but 44psi is usually the MAX psi for a tire. unless its load range E. the door jamb sticker on my two NNBS's are 30psi and 32psi.

other than that. extremely easy pedal from a start. I strive to keep my rpm under 1500 at all time. 60mph max.

It has dht2 Lt 245 75 16. Will it get better mpg with less psi. That's why I was wondering if fuel filter would maybe bump it up 1-2 mpg. Hopefully

---------- Post added at 01:07 PM ---------- Previous post was at 01:00 PM ----------

I'll drop tire psi down any other things I should look at. And I'm guessing the closed open loop comments ate talking about the injectors?

 

[SunlitComet]

closed loop refers to the operating mode of the powertrain computer. try watching this: http://www.youtube.com/watch?v=oG_Xc1nP9aI

you can get a scanner to look at data for issues with tech support here. may want to invest in a scangauge2. can read codes and live data on its display as well as trip function like mileage and tank calculations. mount it where ever the cord will reach and enjoy.

 

[Rangel]

Trust me. I don't have any intentions in visiting Kommiefornia lol