Ok I'm gunna be raked over for this but I'm kinda getting irratated with my truck. I've been having to fill it up a lot more than before my plenum fix.(hate to say but I've been watching my gas gauge a lil bit and it's going down pretty quick with not a lot of driving.) Now I replaced my sparkplugs with NGK V powers and gapped them at .035, I didn't replace my pre cat O2 sensor tho, tires are at the right pressure, and my truck is set with the SCT 87 tune. Not saying I was praying for a mega mileage but I thought I'd get something a bit better with my plenum fix and stuff. Anybody help me out?

 

What kind of mileage are you getting?

If your truck is approaching, or over... 100K miles, it's time for a new front O2 sensor. Disconnect the battery while changing it, so the PCM can relearn how to run the engine.

 

About 9.5-10 all around, even highway.(when I bought the truck I was getting 13-15 average for awhile). I was thinking I should do the o2 sensor but I haven't had time yet.

 

I would just replace the o2, they aren't expensive, and check the cat as well (if you still have one?)

 

+1 on changing the o2 sensor. you can get one from rock auto for about $30 or less plus shipping for a NTK brand o2 sensor which is suppose to be OEM. you can even save 5% if you use a discount code. i just replaced mine less than a week ago and i don't think my gas mileage got any better but i think my throttle response might have got better.
5% Discount Code: 4CE7FDA867AF
Expires: 8/14/2013

 

K I'll do that, thanks guys. And Wombat I don't have a cat either sorry bout stating that.