Gas Mileage Problem

[Zachary Lichliter]

Hi all!



For the last 4 to 5 months or so I have seen a slow but sure drop in my MPG both on the highway and in the city. The MPG is now around 11-13 in city and 14-15 on the highway (just took a road trip about a month ago).



So far I have not noticed any change in the driving of the truck and no CEL so far. The only difference that I have noticed is that I have had an increasingly hard time starting the truck in the morning (takes an extra second or two of cracking).



I have had all the regular scheduled oil changes, changed the air filter, and fuel filter, and changed the tires to brand new tires all done professionally and the mileage just keeps getting worse. The truck is at 70800 miles so I haven't tired the spark plugs and wires yet but they are my next guess as to what may be wrong.



I'm just wondering if anyone else has a better idea to go with here.



Thank you in advance!



Zachary Lichliter

 

[Robert Caffyn]

Question: Did you put a larger diameter tire on the truck? If you did, and you didn't recalibrate the speedo, then all of your readings will be down. It may be time for plugs, wires, some synthetic oil/lubes. How about cleaning the mass air flow sensor(MAF) on your intake tube(use special MAF cleaner). Air filter's no good maybe! Ignition coil(s) may be getting weak. Could be a vacuum leak somewhere too!! Thats worth a look and listen. Take your pick here, any one alone could do it, but 2 or more together can be unbearable to you and the truck. Bob

 

[Allan Reed]

 

[zaffo oxnard]

I was in the same boat. 2001 2WD Auto. Mileage was sucking badly - bad raw gas smell out the exhaust. I did plugs and wires, and saw an increase from 15 to 18 mpg. I got the gap wrong on one plug and ended up with a misfire. Be sure you gap plugs correctly - see sticker under the hood.

 

[Gavin Allan]

For the last 4 to 5 months or so I have seen a slow but sure drop in my MPG both on the highway and in the city. The MPG is now around 11-13 in city and 14-15 on the highway (just took a road trip about a month ago).

What's the problem? That is about what our trucks get.



Ethanol in the gas has lowered MPG by 20% or so.

 

[Bret Langos]

 

[Bret Langos]

I don't know about the rest of the country, but here in the Northwest, every winter we are swithched to the "winter gas" which from what I hear is oxygenated. Not sure what it means, but all my vehicles gas mileage decreases by a good 20% or more. It really sucks. Of course the Tracs pretty much suck gas mileage wise anyway.

 

[Zachary Lichliter]

Hmmm you all are probably right lol. I probably didn't even notice last year who knows. Only time will tell....



Thanks again



Zachary L.