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brat horible fuel milage


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No sir it actually runs good and isnt leaking anywhere. I thought maybe the tire size untill i got to asking but i do alot of trap checking and just slow offroading thru fieldd so i know that hurts it but its gota get better then that? The choke wasnt getting volts so i rewired it maybe itll improve

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I actually didn't expect that response.  Let me make a comparison.  I have a 5.7 liter in my chevy pickup which is more than three times the displacement your engine (and has bigger tires) and gets just a slightly lower gas mileage you are reporting.  Please note that all naturally aspirated gasoline engines utilize roughly the same air/fuel ratio. Given this, you seem to be running an incredibly rich fuel mixture.  So rich in fact that I would have expected it would run very poorly.  Of course if a choke plate was permanently in the closed position, this would richen the mixture but you should have noticed that after the car warmed up. Poor idling, stalling, idle control problems ect. would have been some of the symptoms.

 

I'd do a thorough check for vacuum leaks.  If there are leaks, they would have counter-acted the rich condition and let in air while idling.  

Edited by rain_man_rich
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Are you sure your calculating it right?  WIth 15 inch tires, your tires are going to be turning much slower than they were with the stock 13 inchers.  This means that you will have a lower odometer reading than original.  So...lets say you really drove 350 miles between fill-ups.  Your odometer might only show 200 or 250.  So with that said if you have a GPS you might do well to set it for a known trip of maybe 200 miles roundtrip after you fill-up and then fill it up again and calculate it again.  

 

With that said if your mileage is really that bad then you will be running like absolute crap.  You should be seeing something like 25-29mpg possible better if you drive mostly highway.  Rain-man-rich is right though.  I get 10mpg with my 1991 dodge ram and even that is a bit lower than it should be.  Thats a 4000+ pound 318 v8 though.  Just to put it into perspective.  

 

All i can say is the ordinary stuff to start you off.  Check your timing.  Should be 8 degrees BTDC.  Advance it to 10 for a bit more oomph.  Tune up?  When was that last done.  Wheel bearings?  Are you needing some?  Thats overlooked but if you do a lot of offroading like you say you might have a few screwed up bearings and that will lower your mileage.  Just trying to get you started off.  

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Im going 160 miles and taking 11.5 gallons to fill up. And when warm the choke plate is not fully closed it is not open either. And it has new plugs, wires, filters exhaust is open with flow master, im kinda stumped as to what it could be

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I use a vendor website for tire size comparisons. Go to Discount Tire. There are tabs at the top. Click on "Info Center". About halfway down the column on the left side is "Tire Calculator". Very handy. Enter your stock tire size and whatever you are running currently and you will see the hard data on speedometer/odometer error, difference in wheel rotations, etc..

 

No one has asked if you blow by everyone else in traffic when your speedometer indicates "60". Does the speedometer seem 'slow'?

 

The choke should be wide open shortly after start up. Has the gas mileage problem been long term or just when the unusual cold weather hit your area?

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My bet is on cold weather + short trips.

Especially if you are running non synthetic oil and gear oil.

 

 

Its pretty easy for me to see less than 16mpg in my GL if all Im doing is around town driving, which is 4-5 miles TOPS each trip.

 

Open road even in the winter I normally see about 25.  Summer it creeps right up to 30mpg.

Edited by Idasho
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10 miles it should def be up to temp.

 

Are you letting it fast idle at startup?  

 

Are you running the heater the entire time?  If you run the heater all the time, before it is up to temp, it will only take linger to get up to temp.  A LOT longer.

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I use a vendor website for tire size comparisons. Go to Discount Tire. There are tabs at the top. Click on "Info Center". About halfway down the column on the left side is "Tire Calculator". Very handy. Enter your stock tire size and whatever you are running currently and you will see the hard data on speedometer/odometer error, difference in wheel rotations, etc..

 

No one has asked if you blow by everyone else in traffic when your speedometer indicates "60". Does the speedometer seem 'slow'?

 

The choke should be wide open shortly after start up. Has the gas mileage problem been long term or just when the unusual cold weather hit your area?

This is great! Sure beats doing the math.

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Do you think the coil could be bad making it get horrible fuel milage? Im stumped and some plastic piece in distributor is broke its black has holes in it its under the pickup and mounts for it its a black plastic piece

That surely won't improve your mileage in that state.

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