Was wondering if anyone else has had this happen? When I first purchased my truck back in April the daytime temperatures were relatively cool and my mileage was around 12 mpg/ city driving. Once the summer came around and the temps went up, my mileage went down to 10 mpg/city. I thought that it might have been attributable to the AC being on but I no longer think that is what it is. Now over the last 10 days, the temps have been in the 50's and 60's and my mileage is back up again.
You think it could be a sensor related problem?
Thanks
Chris
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99.5, F250, CC, XLT, 4x4, V10, Auto,Off Road Pkg, Dark Tourmaline, 4" BDS lift, 315/75/16 Durango AT, Eagle 16x10, light tan interior, 6-way Power Seat, Chrome Grill Insert, Clearance Lights, 3.73, LS, Roll-n-Lock bed cover, driving lights photos
Couldn't have said it better myself NoMo.
[img]graemlins/warmimages/icons/smile.gif[/img]
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2000, F-350, SRW, XLT, SC, V10, 5 spd, 4x4, 4.30LS, Short Bed, Off Road Pkg, Camper Pkg, Silver Frost, F550 X Springs, Fabtech Dual Front Shock Kit, with Trailmaster SSV Shocks, Trailmaster SSV Steering Stabilizer, SuperChip, Banks Stinger Cat-Back Exhaust, Borla Headers, K&N Air Filter, Sony CDX-MP450X MP3 player, Infinity reference speakers x 4, Sony Xplod 75W x 4 Amp, Sony 12 Subs x 2, custom sub box...etc.
Same thing happened to me .I live in FLA.and when I made a trip to upstate NY MPGs went up by 2.??
Temp does matter atleast to my truck.
Now that it is alittle cooler down here MPGs went up by 1.3 MPG
I was thinking that if I put a block of ice on my air cleaner I might get even more MPGs [img]images/icons/cool.gif[/img]
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1999.5 F-250 Lariat SD CC SRW LB Loaded V10 auto 4x2 K&N FIPK,Poweraid spacer,muffler deleted,custom seat covers,wood dash kit,tinted windows.BFGs 285s. A-Pillar gauges Tranny temp,oil pres and water temp.Hypertech PP 111 with themostat 160 deg.
ARE Custom Top W/ladder rack,Added a center seat/armrest,Clear corner lenses,TT mirrors, Rancho RS 9000X with incab remote, A work truck you can valet. NRA Life member. My Truck
Las Cruces is at about 3,900 ft, and, everything else being equal, the engine control computer would normally try to advance the ignition by about 4 degrees (typiccally ~1 degree per 1,000 ft in elevation).
However, the nominal engine temp may be a bit high in the summer when local ambient temps are ~100 degrees F and the AC is running. The engine control computer would typically reduce the advance, or perhaps even retard the timimg, to avoid pinging, or pre-ignition.
If local "regular" gas is 85 octane, the engine computer may retard the timing even further under these conditions, and your fuel economy would probably suffer. You might want to try local "mid-grade" 87 in the summer. Ford says this is the minimum requirement anyway.
Otherwise, you got me [img]graemlins/shrug.gif[/img] . My experience withg regular 87 gas (mostly at sea level, left-and right coasts [img]images/icons/wink.gif[/img] ) is that I get worse mileage during the winter due to longer warm-up periods and reformulated winter-blend (oxygenated) gas with lower specific energy content.
However, I use 89 octane (local mid-grade) in the summer when towing. The engine runs much better, I see fewer up-hill downshifts, and the mileage is a bit better.
HTH,
crewzer
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crewzer -- Y2K F250 SD 4X2 CC SB XLT 5.4LV8 AT 4.10LS
I use 87 octane all year round. I agree with the ice block, going to put an LN2 (liquid nitrogen) tank on my radiator and see if I can get 30 mpg. [img]images/icons/laugh.gif[/img]
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99.5, F250, CC, XLT, 4x4, V10, Auto,Off Road Pkg, Dark Tourmaline, 4" BDS lift, 315/75/16 Durango AT, Eagle 16x10, light tan interior, 6-way Power Seat, Chrome Grill Insert, Clearance Lights, 3.73, LS, Roll-n-Lock bed cover, driving lights photos
Cooler air will improve performance/mileage...to a point. I've noticed that when the temps here get into the 30's, the mileage gets worse. Probably due to much longer warm-ups and "rich" fuel conditions. Couple that with oxy-fuel, and say good bye to 1 1/2 mpg [img]images/icons/mad.gif[/img]
I'm not sure what miles your rig has, but they also improve mpg as they break in (1000-1500 miles)
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Y2k F350, white with harvest gold trim,V10,4x4,Lariat,SC,Auto,Tow pkg,camper pkg,ESOF, so-called limited slip, off road,3.73,Rancho 9000 w/ in cab control, Ride Rite Air Bags,Long bed,Rickson 19.5" wheels, Michelin XDE-MS,Lance Camper, BugDeflector2, Stull Grill, KN., Flowmaster 50
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