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kydamcat

My MPG has dropped big time

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In Sept. I started having problems in my 98.5 with the torque converter at about 40 mph,tack dying, and sometimes no start every time. Milage dropped from 19 to 16. Dorkweed? said it was the crank position sensor. I was working 6 12's and driving 150 miles to work. I drove it until mid Dec. when I had time to fix it. It drives like a charm now, check engine light is off. Milage is still at 16. I think I need some more advice on the mpg.

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I would check for codes first. Even though the CEL is off. Has your fuel pressure dropped as well? When did you last change your fuel filter?

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No codes at AutoZone. Fuel pressure about 16. Changed fuel filter in Aug.(12000 mi. ago) Mileage dropped at the next fill-up after I started having problems.

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No codes at AutoZone.

Good...

Fuel pressure about 16.

Is the WOT pressure or Idle??? We need WOT pressure...

Changed fuel filter in Aug.(12000 mi. ago) Mileage dropped at the next fill-up after I started having problems.

Fuel that are high cetane tend to produce extremely low MPG's. This tank of fuel is doing this try running out this tank and buy fuel from some where else...

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My best guess is that's it's a combo of "winter fuel" and "bio blended fuel". I go to KY regularly and just like here at home, y'all have bio-blended diesel sold at many of your stations. My mileage is down from last winter. I think they're upping the bio in the fuels sold around me. All that said, it has been real cold the last 2 weeks though and that doesn't help either!!:smart:Remember also that along with the above; the fluids in your engine, diffs, tranny, and transfer case are thicker and flow less easily in colder weather. It takes more energy/fuel to overcome/heat it up. Also, in the winter time, the outside air is denser and slightly harder for your truck to push through. Not much but it's measurable.

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My best guess is that's it's a combo of "winter fuel" and "bio blended fuel". I go to KY regularly and just like here at home, y'all have bio-blended diesel sold at many of your stations. My mileage is down from last winter. I think they're upping the bio in the fuels sold around me. All that said, it has been real cold the last 2 weeks though and that doesn't help either!!:smart: Remember also that along with the above; the fluids in your engine, diffs, tranny, and transfer case are thicker and flow less easily in colder weather. It takes more energy/fuel to overcome/heat it up. Also, in the winter time, the outside air is denser and slightly harder for your truck to push through. Not much but it's measurable.

So very true...:thumbsup:

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Have you checked your brakes? I had the fronts rust seized & dragging. It drove me nuts, dealer told me "no codes" nothing wrong with it! Truck has so much power, I towed for a year before an inspection found it. Russ

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Have you checked your brakes? I had the fronts rust seized & dragging. It drove me nuts, dealer told me "no codes" nothing wrong with it! Truck has so much power, I towed for a year before an inspection found it. Russ

Another valid one... I had my rear caliper bind up there pistons...:eek:

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I have been getting logged out when I try to post so I hope this works.WOT pressure -11 @2000rpmRefueled at 4 different stationsmileage dropped when the crank sensor started malfunctioning in Aug and has stayed down. Brakes were just inspected 3 days ago. good shape.New fuel filter in Aug. had 3-4000 mi on it when the crank sensor went out.Mopar; I really appreciate everybodys help. A 12V I can handle, these 24V's are something else.

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How ' bout something simple like your air cleaner? BHAF?I thought BIO fuel boosts MPG & performance up till B20. Least that's what i've read & heard from people that I've have high admiration for.

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Mopar- Haven't done a valve job yet. On the list after layoff.K&N filter was cleaned in Aug. Just checked it , looks ok.IAT is coming out at the first chance.I think I am going to synthetic in everything this summer.Thanks for all the help.

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Mopar- Haven't done a valve job yet. On the list after layoff. - Really good chance the valve lash is getting to wide on you!

K&N filter was cleaned in Aug. Just checked it , looks ok. - Double check that K&N for holes if you hold it up to bright light and see pin holes throw it away! BHAF doesn't require any maintenance for over 6 years! I've got one now with over 110K miles and still going...

IAT is coming out at the first chance. - If you got a exhaust brake it will be dirty if stock no need to clean...

I think I am going to synthetic in everything this summer. - Not required... I'm pullind 25.3 MPG with Petroluem base lubes in the summer...

Thanks for all the help.

Comments in blue...

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Mopar- Haven't done a valve job yet. On the list after layoff. K&N filter was cleaned in Aug. Just checked it , looks ok. IAT is coming out at the first chance. I think I am going to synthetic in everything this summer. Thanks for all the help.

Throw the K&N away as fast as you can especially if you drive in any kind of dirty conditions. I have my own personal oil samples to prove they are junk along with others testimonials of having bad oil samples and dirt inside the intake system as well.

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Throw the K&N away as fast as you can especially if you drive in any kind of dirty conditions. I have my own personal oil samples to prove they are junk along with others testimonials of having bad oil samples and dirt inside the intake system as well.

:agree::whistle:

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I have used 3 tanks of fuel and I am now getting 18 mpg. (don't know why)keeping the rpm under 2K.Blame the winter fuel for not getting back to 19mpg.I'm happy now!!!!

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Hmmm... At least you back to some normal numbers. I wonder if the station your buying from is adding more cetane booster and anti-gel themselves... Several station up here hide 52 gallon barrels behind lock fences or behind the store with additives... Look at the lower right corner...(Good ol' paint thinner) :wow:post-2-138698163122_thumb.jpg

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