bad gas milage after tb clean

[fallen angel]

Previous to cleaning my throttle body I could hypermill to 20mph with where I drive. I did disconnect the battery when I was cleaning. Now I'm hard pressed to get better than 17mpg. It seems to have much better milage when warmed up, but that seems to be an observation based only on me desparately trying to hypermill higher. Maybe I didn't clean the throttle body well enough?

06 4.2

[TBYODA]

Did you pull the TB off and clean the inside? BTW pulling battery risks damaging hvac actuators but better now than on vacation. You can reset PCM by pulling fuses 10 & 28 and wait like 15 min. Did the TB start and run rough for a couple mins as it relearned? You may have also see the CEL come on/off a bunch of times, did in mine when I did this.
What is your mileage, if high you could be ready for some plugs. ACdelco Iridum #41-103 only.

http://m.youtube.com/watch?v=VdvgsaDmkac

[fallen angel]

Didn't run rough or anything. I've got about 95k on it. Time for a lot of maintenance work, though this change was rather instant. I did clean the inside of the throttle body.

[Trail X]

Is this one trip, or multiple averaged?

If one trip, give it time. There's a lot of variables when it comes to gas mileage.

Throttle body cleaning really shouldn't affect gas mileage at all. Cleaning the body really only affects the ability for the throttle to properly meter air for idle.

If you indeed are seeing a fall in your mileage over multiple trips, that began with the the cleaning, I'd have to suspect that a sensor somehow got fouled in the process of the cleaning.

[HARDTRAILZ]

James nailed it...

[fallen angel]

Multillt gas tanks. Suppose its time for a new o2 anyway.

[Trail X]

Any other details? How long were these drives? I assume you live in a cold climate? Cold weather really sucks a lot of extra energy out of the combustion chambers to warm the engine up, it won't affect long drives gas mileage as much (upwards of 40 miles at a time), but on shorter drives you'll generally see a decrease inversely proportional to the length of the leg of the trip.

[dvanbramer88]

You'll also typically lose a mpg or two with winter blend fuel.

Also, letting the truck idle in the driveway to warm up hurts fuel efficiency. And it can actually make the truck take longer to reach operating temperature and keep you in the low efficiency state like James talks about longer.

[jonbo2002]

I used to average 20 in the summer and 17 to 18 in the winter here in MI.

[fallen angel]

I don't let it warm up very long, just enough to get oil moving about. Drives are the same, about 15 miles each way or longer at times (sure is nice to have a short drive!) Perhaps it could be the fuel and cold mixed, but awefully funny that I can trace with certainty that it dropped lime a rock after I did the work. I got the throttle body mostly clean, only with very little stuborn carbon on the intake plenum side still there, but it isn't built up or obtrusive. I had the throttle body off for the cleaning as well so nothing got intk the intake. Just very strange how this all happened.

[Trail X]

Well, keep an eye on it. I'd imagine most of it is due to the cold and fuel, but if it continues to fall, you'll want to look closer. In all reality, 17mpg isn't too bad.

[jhmeg2]

if I could get 17 I would be gitty. I'm at 10mpg. I mean yeah the 6" of lift on 35" tires.... but really, even if I swap out for stock wheels, I get 12ish..... maybe I need O2s. I just cleaned throttle body, and new plugs and oil change... HELP

[Trail X]

That's pretty dismal, but par for the course for some members. Need more information. What driving is this? Highway, city? If highway, what are your speeds? Do you have a scangauge or torque program to monitor things in the engine? What's your water temps looking like? Does your transmission unlock the TCC a lot on the highway? More info is needed.

[mikekey]

Knowing what his gears are would help too. That's about what we get around town. About 12mpg -13mpg on our trip to Kentucky with 3.73's and the 35's. This is why I need to get off my lazy butt and get around to the 4.56's.

[Moots1288]

I get 10-11 in the city with 3.73s and 33s on steel wheels.

[TBYODA]

I get 10-11 in the city with 3.73s and 33s on steel wheels.

Plus you got your spare tire up top, you need a tire carrier. Get Jason to weld you up one.

[Moots1288]

My spare tire sits in my trunk when im home.. thanks

[mikekey]

I can barely lift my tire into my truck, how you get yours on the Roof is beyond me. I need Jason to weld me up a carrier! How much cash you want Jason? lol..... eventually I'll get my own welder.

I'm surprised Moots is getting the same milage. But I bet he has more stop and go than me.

[Moots1288]

I can barely lift my tire into my truck, how you get yours on the Roof is beyond me. I need Jason to weld me up a carrier! How much cash you want Jason? lol..... eventually I'll get my own welder.

I'm surprised Moots is getting the same milage. But I bet he has more stop and go than me.

Need to get those muscles man! Its not so bad getting it up there, I got steel wheels they're heavy as shit

[dvanbramer88]

Before Josh moved to VA I stopped by his house to visit for a little bit. I helped him put his tire on the roof. I climbed up on the roof and he rolled the tire up the quarter panel and C pillar. I grabbed it and flipped it over into the basket.