fuel milage problems

[joeseabee]

I have searched this section and had no luck. I was hoping someone could give me some help. i have been getting relly bad gas milage lately and im not sure why, or if there is anything i can do to improve it. I used to get abour 17 and now im down to about 14.

I have an 03 3.3l cc with 120,000 miles.
I had the timing belt and all hoses replaced about 10,000 miles ago.
It gets regular oil changes and has a new air filter.
I also got new tires and have them serviced regularly too.

This truck has also been getting a little slugish and i try really hard not to step on it to bad, but its just not like it once was.

any help would be greatly appreciated.

[Jrjones]

What condition is your distributor in? Spark plugs? Any hesitation/misfiring occuring?

[joeseabee]

i dont think so, when it was in the shop for the timing belt they said everything else looked good.

[joeseabee]

is there anyway i can change the gearing on it. if i put the cruse on at 70 or more it down shifts alot to maintain the speed and its running hard at 3000+ rpm's. If I could keep it at higher speeds and lower rpm's like most cars I think that would help. my wifes v6 chevy trailblazer runs 75 at 2000 rpms on cruise.

[Jrjones]

Do you have a supercharger? Check for a knock sensor code. I've read that other people with automatics have noticed a lower cruising rpm with a new (working) knock sensor.
I have a manual so it didn't anything with cruising rpm (obviously). I am at about ~2800 rpm when at 70mph, if I remember correctly

[jerryp58]

The change didn't occur after the timing belt replacement, did it? If so, they may have messed up the timing.

Fuel filter? Exhaust restriction (converter)?

[joeseabee]

thanks for the replys guys.
it does not have a supercharger, does the non s/c have a knock sencor too?

the gas milage was fine after the timing but the power loss seams to have been fading for a while.

[sonora]

Originally Posted by joeseabee

thanks for the replys guys.
it does not have a supercharger, does the non s/c have a knock sencor too?

the gas milage was fine after the timing but the power loss seams to have been fading for a while.

Yes your non s/c 3.3 has a knock sensor. Have somebody read your trouble codes. It is a common problem for them to go bad. This WILL NOT make your SES light come on.

Also you may want to check all your oxygen sensors for proper operation.

[joeseabee]

thanks for the input guys. keep it coming, I have a friend that is a michanic im gonna see what he can look up for me.

[Jrjones]

Although I had a faulty knock sensor and I did the relocation mod (see the sticky at the top of the page), I didn't notice a big difference in fuel mileage with a working knock sensor.
The s/c guys notice a difference in performance though.