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12 Mpg - What Do I Do !

rschultz

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rschultz New Member

rschultz

Posted
Posted

My daily driver is a 2001 Silverado 1500, 4wd, 5.3L, 165,000 miles.

 

The gas mileage just plain sucks! By my calculations, I am only getting 12-13 mpg! I know its capable of better, because I've seen it. Started noticing it going downhill last fall.

 

K&N filter, new Bosch plugs, oil change every 3000, tranny service 3 months ago, SeaFoam cleaner every other oil change. I dont know what else to do.

 

Do I need a new injector? sensors? coil packs? PLEASE HELP!!

jf781 Enthusiast

jf781

Posted
Posted

Get rid of your bosch plugs and get delco. Won't fix it entirely but will help.

 

Have you cleaned your MAF? CEL? Have access to a scanner to see if there are any codes at all.

 

How long have you owned it. If a long time what kind of mileage have you gotten before. This city or highway driving.

 

May sound stupid but have you changed tires/size/ checked air pressure recently

 

It's also cold (depending on where you live) so that won't help. I typically see 1-1.5 MPG drop during winter vs summer.

 

Welcome to the forum. Need pics of your truck otherwise we send all of your posts to a nissan forum.

redvett Senior Enthusiast

redvett

Posted
Posted

What was your fuel mileage earlier. Did you take in the fact that winter gas along with the addition of ethanol will hurt fuel economy? What modifications have you done to your truck, bigger tires,cold air intake? How much junk do you carry in your vehicle and has it been tuned up lately? Give us more,all info.

rschultz New Member

rschultz

Posted
  • Author
Posted

Figured was getting 15-16 in the summer. Mostly highway driving. I realize winter fuel reduces the fuel economy, but this seems a little extreme.

 

Have owned it 6 years No mods other than a k&n filter. Dont carry much besides the spare & my tool box. Tire pressure is ok.

 

Not to sound stupid, but Ive never cleaned a MAF or CEL before. Just take them off & clean? Any special cleaner?

 

Thanks again!

redvett Senior Enthusiast

redvett

Posted
Posted

Clean the MAF but the "CEL" is the check engine light and doesn't need cleaning. Ditch the Bosch plugs for AC Delco's.

 

Figured was getting 15-16 in the summer. Mostly highway driving. I realize winter fuel reduces the fuel economy, but this seems a little extreme.

 

Have owned it 6 years No mods other than a k&n filter. Dont carry much besides the spare & my tool box. Tire pressure is ok.

 

Not to sound stupid, but Ive never cleaned a MAF or CEL before. Just take them off & clean? Any special cleaner?

 

Thanks again!

Nytemare Senior Enthusiast

Nytemare

Posted
Posted

Is this your first time driving it in the winter?? Winterized fuel contains a lot more ethanol...and even more this year than before by some accounts. Bet you will go back to your normal 15mpg area once late spring hits and all the winterized fuel is gone.

6.0max Enthusiast

6.0max

Posted
Posted

dont forget that during the winter mornings that you truck heats up in front of the house...this is dead millage...i do 60miles less on a tank durring winter

jro909 Senior Enthusiast

jro909

Posted
Posted

i second ditching the bosche plugs, did you ever do the wires? do you drive the city alot? i average about 17 between city and highway driving on my 5.3, but i also drive like old people screw...when you say your tire pressure is ok, as in what psi? i lost 2-3 mpg on my old set of stockers from being so low and beat up

Nytemare Senior Enthusiast

Nytemare

Posted
Posted
i second ditching the bosche plugs, did you ever do the wires? do you drive the city alot? i average about 17 between city and highway driving on my 5.3, but i also drive like old people screw...when you say your tire pressure is ok, as in what psi? i lost 2-3 mpg on my old set of stockers from being so low and beat up

BAWAHAHAHAHAHAHAHAHAHA

:rolleyes::lol::lol::lol:

 

 

Third on the "Botch" Plugs

 

NGK TR-55, or AC-Delco stock replacements.

MaForrest Enthusiast

MaForrest

Posted
Posted

Bosch plugs blow pig weiner. Seriously...they do. And I would be happy if thats what I was getting for milage. I average 9.8 mpg and 8.1 while towing the jeep. Hows your front and rear ends? Both roll freely? Front end not slappin all over the place? Any resistance, even if its a little, will suck the fuel super bad. With my lift and tires ( 5.7L by the way) I was averaging 15.6 freeway and 14.2 in town. Front end wears out and I'll drop to single digits.

redvett Senior Enthusiast

redvett

Posted
Posted

Fourth on the plugs. I don't know what it is with people trying to invent the wheel er spark-plug. If GM could have gotten more power & performance out of a Bosch or any other plug they would have used them. Believe me the the dyno at the GM Techcenter try everything avaliable.

jblakeney Senior Enthusiast

jblakeney

Posted
Posted
My daily driver is a 2001 Silverado 1500, 4wd, 5.3L, 165,000 miles.

 

The gas mileage just plain sucks! By my calculations, I am only getting 12-13 mpg! I know its capable of better, because I've seen it. Started noticing it going downhill last fall.

 

K&N filter, new Bosch plugs, oil change every 3000, tranny service 3 months ago, SeaFoam cleaner every other oil change. I dont know what else to do.

 

Do I need a new injector? sensors? coil packs? PLEASE HELP!!

 

Any DTC's?

 

Get them cheep plugs out of their...... Get some AC DELCO's OR NGK's.... They are going to be 7-12 bucks a piece...... Thats life...... (just me here but what ever it had is the best thing the GM could come up with)

 

But im with some of the others. Have you been warming your truck up in these cold winter mornings?

 

I get 16 does not matter how I drive my truck.... City, highway, like I stole it......

 

My 3/4 nbs gets 12. It has ALWAYS got 12 unless it has a heavy trailer behind it.

 

Jbo

frdfandc Enthusiast

frdfandc

Posted
Posted

Change out the spark plugs.

 

The other thing you can do is have the O2 sensors monitored. With 165,000 miles on the clock, I'd be willing to bet that they are lazy. Unless they go out all together, the Check Engine Light will not illuminate. The O2 sensors switch from a lean to a rich condition very quickly. This helps with fuel consumption and emissions. If they are slower, then this will kill fuel economy.

 

In one of my Chrysler training classes at the Chrysler Training Center we did this with an older car - 3-4 years old with around 80,000 miles on it - company car. We monitored the original O2 sensors, then swapped in new O2 sensors. The original sensors switched from lean to rich much slower than the new ones.

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