Getting worse gas mileage than before
01-27-2012, 04:02 PM
#22
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I've gotten 400 miles on a tank all highway on the east coast before, also. I've also gotten in to the low teens for hard core city driving with the same car. Between carbon cleanings, my mileage drops off 4-6 mpg across the board. Maybe that's all that you need? I doubt new wires will do anything but spend money better placed elsewhere. (If it were a spark issue, your car would lean you out.)
01-27-2012, 04:49 PM
#23
It's possible...but I've kept my engine pretty clean, well as much as I can do. Always used Mobil 1 or Castrol Syntec every 5k miles, Techron fuel system cleaner every 10k or so, and I did the full seafoam treatment back when it had like 35k miles. My friend that swapped out the rod said everything looked fairly clean. I can understand if my mileage gradually decreased over time, but this was fairly sudden. I did not get this kind of mileage before the engine hydro locked.
Again, the only way mileage can drop off suddenly like that is with an 02 sensor(s) issue.......unless someone hooked up a trailer hitch and strapped a 34" Fountain boat with triple 300 Merc outboards to the hitch.....lol
The whole thing about using certain fuel to keep fuel systems clean....is a hoax. Gasoline is a great fuel injector cleaner, them adding some special chemical to the gas is the biggest marketing gimmick going.
One can of SeaFoam in 1/4 tank of gas every 3-4 months is all I've ever done for 14 years now.
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01-27-2012, 04:57 PM
#24
Also....another failure that can cause a drop off in mileage like you're getting....a badly leaking fuel injector.
But if its that bad, you will usually got a cylinder bogging down/misfiring/backfiring.
You said its running "better than ever".....
But it can't hurt to check to see if you injectors are holding fuel under pressure.....
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But if its that bad, you will usually got a cylinder bogging down/misfiring/backfiring.
You said its running "better than ever".....
But it can't hurt to check to see if you injectors are holding fuel under pressure.....
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01-27-2012, 11:29 PM
#26
It's possible...but I've kept my engine pretty clean, well as much as I can do. Always used Mobil 1 or Castrol Syntec every 5k miles, Techron fuel system cleaner every 10k or so, and I did the full seafoam treatment back when it had like 35k miles. My friend that swapped out the rod said everything looked fairly clean. I can understand if my mileage gradually decreased over time, but this was fairly sudden. I did not get this kind of mileage before the engine hydro locked.
