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I am new to this forum and just bought my first Ford. Own 2 second generation dodges one gas and one diesel. Always wanted an older Ford.
I found this one on craigslist. It is a retired fire department truck and in really good shape (for the northeast) and with the service body I couldnt pass it up. It is a 1989 Ford F250 with a 351W, C6 Automatic and 4:10 gears. Besides wanting to stall once in a while when I stop at a stop sign, the truck runs excellent. I bought it primarily for a farm truck and to hold all my tools.
I love this truck, but one issue that I could use help overcoming.... the fuel mileage! I knew it wasnt going to be great, but I am getting about 6 mpg. I drive it like an old man too. It only has one tank and I'm guessing its around 18 gallons. I can go about 100 miles and then need to fuel up. On the highway I dont go over 55 with it. My house to the farm is 2.5 miles.
I like the truck, one thing I have noticed is firedepartment trucks are almost ALWAYS in perfect condition body wise. Now on the engine, we had a F-350 with a 460, 4:10 gears and a manual transmission, not sure of the style tranny, but we got MAYBE without a load a good 5 mpg on highway. With a load maybe 3. Those old trucks definitely hogged gas.
F250, 4x4 no overdrive and you are taking trips to the farm that barely get it warmed up, not sure much you have loaded but they are not the most aero. Best you can do is a good tune check to make sure brakes are not dragging and tire pressure is up. But you didn't really buy it for mileage, but it should be a little better.
Thanks for the input. Brakes are good. No drag. Front has new rotors and calipers. My buddy wanted to sell me his 98 super duty with a 5.4 triton and 4 speed auto. Bed and body are pretty rotten, but motor and tranny are good shape. Anyone know what the chances are it would work in this truck? He wants to sell it for $500. He consistently gets 13-14 mpg. Worth the hassle?
Start by running the Key On Engine Off ( KOEO ) tests. Then see if there are any stored codes. 6 MPG is really low so start with the basics. ....code check, plugs, wires, cap and rotor. Then filters.
I will check for codes. Previous owner changed the throttle position sensor and air control sensor I believe it's called. Said there was a code and the mechanic said it was for that. Also looks like plugs and wires are new. One thing I haven't done is fuel filter or air filter. Would fuel pumps have anything to do with it? Probably not? Can anyone explain how to check the rotor?
welcome to FTE.
if it has new plugs and wires, the cap and rotor are probably new also.
stalling when coming to a stop could be a dirty idle air controller, or a dirty throttle body.
6 mpg is pretty bad, you should be seeing closer to 9-10 mpg with the C-6 and 4.10 gears..
you will have better luck trying to knock down a 12 inch thick concrete wall with your head than you will trying to stuff a 5.4 and 4R100 in that truck.
Yeah I have been doing more research on it and found that it really isnt worth the hassle to put that 5.4 in there.
I'm trying to figure out if maybe my o2 sensor is bad? The truck has a strong smell of gasoline when running, but no leaks anywhere. Thought about checking a few spark plugs and see what they look like. I know this is a truck, I am just really hoping to get 10-12 mpg with it I would be satisfied then. I dont drive over 55 with it, with my short trips there is no need to, but wondered about maybe an overdrive transmission that would bolt up? I'm thinking though that my motor has the issue for fuel mileage over my driving habits.
it could be a bad 02 sensor.
is the check engine light on? that will give you hints as to what the problem could be.
an overdrive trans can be swapped in, but you will also have to do some electrical modifications to make it work. C-6 is all mechanical, the OD trans is computer controlled
Yeah you're way low on mileage even for that truck. If it smells like raw fuel then it's running way too rich. You'll probably have a fault code or two in the computer to help you decide what to do next.
another thing i just thought of, if the fuel pressure regulator is not working properly it may have high pressure, making the engine run rich. that will also cause low fuel mileage and make the exhaust smell like raw gas.
another thing i just thought of, if the fuel pressure regulator is not working properly it may have high pressure, making the engine run rich. that will also cause low fuel mileage and make the exhaust smell like raw gas.
I read you can put a vacuum line on the fuel pressure regulator and try to suck air and if you can it's bad. Is that correct? Looks like they are $25 at local auto parts.
Truck does have some codes on it. I'm trying to understand how to decode them. I had a bunch of single "1"s, and then 4 sets of 3. It wasn't warmed up so I am going to go for a ride around the block and try it again.
Not much to add, get codes first, before anything else. That should set a course of action. Doing the Sixlitre tune-up will also help once any codes are cleared, and if you're feeling adventurous, maybe even running Seafoam. One cheap thing you could do right now and has no downsides would be cleaning the throttle body, get a throttle body cleaner spray and try it.
