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Discussion Starter · #1 ·
So this is an older truck and I'm finding that the forums here are generally about 99-later trucks. So...I figured I'd ask specifically.

I just filled up yesterday and I'm not getting great mileage. From a 350 with throttle body injection and mixed driving I had hoped for around 16mpg. I ended up getting 13 and change.

The truck was really well cared for and even though it has a ton of miles (273k) it runs great because the engine and transmission have been recently rebuilt. That said, I don't know what might have been done by the previous owner as far as mods. I know he didn't leave everything stock - the most noticeable thing is an HID headlight kit.

So I'm looking for things I can do that will help mileage.

The first thing I'm thinking of doing is putting in an electric fan. Right now the truck has a fan on a clutch. Will this change make much difference and more importantly, is there a place to put a sensor for the fan?

Another idea was replacing the paper air filter with a K&N. Is that a good idea and will it make any difference in fuel economy?

Any other ideas before I spend a ton of money on a chip?
Coil? Exhaust? General cleaning, etc?

Edit: I was just out loosening the serpentine belt which was way too tight and took note of the name of another accessory that has been added: Taylor Power Tower throttle body spacer. Is that helping or hurting. I haven't gone looking for info but it seems kind of like a gimmicky sort of gadget. Is it legit or a dud?
Thanks
 

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A cold air intake, along with a cat-back exhaust will probably get you up to the 16mpg area. After that maybe a programmer.
 

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ARoadRaginCajun said:
A cold air intake, along with a cat-back exhaust will probably get you up to the 16mpg area. After that maybe a programmer.
+1 ^ But I would also look at if you are getting 13 mpg right now and wanting 16 mpg, would spending the money on these accessories actually pay you back in the long run for only 3 mpg.
 

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In my experience with those old TBI's the best thing you can do is keep it really clean. Make sure you use good quality fuel, keep that jet on the throttle body nice and clean, and run some seafoam through every now and then. As for the air filter, I can definitely say that I noticed a difference in putting one in. It would be really small as far as power and mileage go, but still a noticeable difference. Even though they seem expensive, the fact that you can clean them up and reuse them a million times makes up for it in the end.

As for your exhaust I recommend keeping it factory sized. Meaning the same size pipe all the way through and a similar muffler as came with stock. Anytime I put in a big free flowing muffler or expanded to a larger diameter pipe I definitely felt some more power but the mileage went down significantly. The catalytic converters on those exhausts also had a bad habit of clogging up and sucking a ton of power out, so I would recommend checking into that, as well as the muffler if it looks like it might be pretty old. The O2 sensors were also a really common cause of crappy mileage and CEL's

I have to apologize to the above poster but I will disagree about the cold air intake. Unless you're running the truck at full throttle (which you shouldn't be if you're looking for good fuel mileage) the CAI won't make any difference other than a little growlier sound.

As for your throttle body spacer, it's not hurting anything and if anything might actually do what it's supposed to and help mix the fuel a little better for a cleaner burn, which is good. I'd leave that where it is.

The "Chips" you can get for those older motors were all too often just a resistor that jacked up your fuel ratio and got you a bunch of power and ate up all your fuel. If you see one for 60 or 100 bucks, I'd pass on it. As for an actual programmer, I've never used one on those older motors. They didn't really have an overly complicated computer setup with VVT and stuff like the newer ones do, so I wouldn't suspect you would get your money's worth out of that, but again I've never used one on an older motor like that so I can't say for sure.

When you say coil, if you mean one of the high power coils to replace the old cap and rotor (can't remember if 94's still had those) Then yes that is a great investment. They are easy to install, pretty cheap and make a world of difference in how the truck runs. Definitely would recommend that if it has a cap and rotor type distributor. Also make sure you have a good set of decent quality, properly gapped plugs in because that will also make a huge difference.

As for your idea of getting an electric fan, that will work nicely. An electric fan keeps the engine nice and cool at any rpm and is generally more efficient. The change in mileage will be very slight, but overall it's a great upgrade that you can do for pretty cheap on those engines. I would typically just slide the temperature sensor in between a couple of the rad fins or even strap it right to the upper rad hose.

Most importantly just try to keep your foot out of it. Hard acceleration kills mileage like nobody's business and an extra 5 or ten miles per hour on the highway makes a big dent.

Hopefully those suggestions help a little!
 

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Discussion Starter · #5 ·
ZSilv71 said:
ARoadRaginCajun said:
A cold air intake, along with a cat-back exhaust will probably get you up to the 16mpg area. After that maybe a programmer.
+1 ^ But I would also look at if you are getting 13 mpg right now and wanting 16 mpg, would spending the money on these accessories actually pay you back in the long run for only 3 mpg.
Indeed. I didn't buy a new truck so obviously I don't have surplus cash laying around. I probably won't consider upgrading to a high flow exhaust until it's time to replace my muffler anyway unless a deal comes along. Also I should point out that this will not be a daily driver. I bought it for occasional hauling and hunting. So...increasing mileage is more of a want rather than a need.

As far as the intake, the filter housing is connected to a box that is fed from a hole in the side of the engine bay. So I'd conclude that the air is coming from outside already and is more-or-less acting as a cold air intake already. Am I mistaken?

Thanks for the replies.
 

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ARoadRaginCajun said:
As far as the intake, the filter housing is connected to a box that is fed from a hole in the side of the engine bay. So I'd conclude that the air is coming from outside already and is more-or-less acting as a cold air intake already. Am I mistaken?
[/quote]

Well yes and no. "Cold Air Intake" is just a name some company originally came up with to help sell the product. They are generally place in such a way as to get the coldest, highest density air into the motor possible, and also generally have a fair bit less restriction to flow. That being said, the difference is really only noticeable at wide open throttle, which coincidentally is the point where they take all of their horsepower gain information from when the advertise. Helpful if you're racing or mud bogging, otherwise not that great IMO
 
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