mpg dropping like a rock!
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Joined: Nov 2009
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mpg dropping like a rock!
I don't know what is up, but the last 2 tanks, the truck gets like 8 mpg! Mods are Banks headers/y-pipe/3.5" cat back, stock cat, banks ram aie, w/ fresh cleaned filter,5-star tuner, fresh oil, fuel filter, and I cleaned the maf and tb. I need to do plugs and O2's (117k on originals), but I can't see that causing the massive drop, used to get 10-12 depending on mix, now 8 even on freeway at 70. drove 60 miles last night and used nearly 1/2 tank!!
Thing is, the motor runs smooth as glass, and monitoring the pids from the scanner shows nothing out of the ordinary.
Any ideas?
Thing is, the motor runs smooth as glass, and monitoring the pids from the scanner shows nothing out of the ordinary.
Any ideas?
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Joined: Jul 2002
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From: Long Island USA
Could be the winter/summer blend gas, although that should have already happened a while ago, regardless of where you are. Change gas brands lately?
But 8 on the highway? Sheesh. That's horrible. Check your fuel pressure, should be 28-30 at idle, 38-40 at high load (or disconnect the vacuum to the fuel pressure regulator at idle, and it'll go up to 38-40).
But 8 on the highway? Sheesh. That's horrible. Check your fuel pressure, should be 28-30 at idle, 38-40 at high load (or disconnect the vacuum to the fuel pressure regulator at idle, and it'll go up to 38-40).
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lol, I know it is not a boat anchor, or a trailer, since the truck instantly gets 6 mpg the moment it sees a trailer! Maybe.... I have been parking it in the back, next to my car trailer, maybe the truck thinks it will be towing!
I will have to check fuel pressure, and I think I will pull the maf again and clean it, maybe the filter oil got on the wires, idk.
I will have to check fuel pressure, and I think I will pull the maf again and clean it, maybe the filter oil got on the wires, idk.
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Tuned
Joined: Apr 2001
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Just a quick thought, are you sure no one has been siphoning fuel from your trucks or maybe you have a small leak in your tank? If it is small enough, the fuel would evaporate and not leave a puddle.
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Seems like my mileage has crapped too. My exhaust mods are almost identical to yours(OP) except I use stock intake pieces and no software. I was thinking that the power enrich was on all the time(not sure if these trucks have a power enrich? Feels like it does). I was guessing at the PE because, like you my idle and driving characteristics are flawless and smooth. I was thinking about posting asking if anyone knows about the power enrich and if it can get stuck "on", was unsure..dont wanna get flamed.
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batviper
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