Horrible Mileage in a '92 F250 burning WVO

[basilbowman]

Hey guys,

I got my truck up and running, and it's doing ok, but it's getting about 8-9mpg and I've heard that's up to half of what I ought to be getting. The tach is dead, the guy I bought it from unplugged the sensor on the front of the engine because he said it w2as bad and causing it to shift funny, so I'm thinking that's got something to do with it - anybody know how to check one/where to get a new one? I don't even really know the part I need, it's a cylinder about three inches long with about a foot of wires coming off of it, then it snaps into a coupling connector with a wire going up into the dash, it looks like, but this is all more or less guessing at this point, I've not gotten a chance to go confirm anything. Also, I stalled out today with a clogged fuel filter, even though this only has about 800 miles on it, leading me to think that it's probably just jetting the fuel in about as quick as it can, which is probably way too fast. It doesn't sound like it's racing all the time though, it sounds about normal. Any thoughts?

-N

 

[Shadetreemechanic]

I've got an extra tach sensor we can throw on there. The e4od will not work correctly without the tach sensor hooked up so it has been running in limp mode the whole time you have had it.
Try to limit your driving until you get this straightened out. Limp mode is ******* these tranny's because line pressure defaults to maximum. Your torque converter has probably also not been locking which has contributed to your bad mileage.
I am wrapped up all day today, but stop by my office Friday or next week and we can take a look at it.
Nate

 

[basilbowman]

That's about what I figured - but the guy I bought it from swore up and down that it was fine to drive, it would be better to drive it disconnected rather than connected but broken. Anyways, there's 1,500 miles I wish I hadn't put on it. I can come to wherever you are, my job is flexible enough I can grab 15 minutes whenever. I'm fine dropping it in there myself - and I've got to drive back to Cowan after work tonight - is another 20 miles after 1.5k going to be the end of the world, or should I come by your place tonight, pick it up, and just screw it in in a parking lot somewhere before I drive home?

-N

 

[icanfixall]

Wow is all I can say at this point... These auto trans must have imput from several sensers to make them function properly. The tach senser is just one of them but its very important too. The guy selling you the rig will tell you anything to sell it. He is completely wrong about not needing a working tach senser. If the truck sat for a long time the fuel may have some agle in it causing the filter to plug up. Or its not a filter with just 8000 miles on it. Did the seller tell you thats what it was... You need not worry much but... Get the tach working or the trans will be ruined. The hard shifting and slipping clutches is just to get you to a dealership. Not to just drive it and look the other way about the issues. Sounds like you have someone near by thats helping to out with good advise. Thats good to know. Welcome to the forum and ask any questions you want. This site has seen all of them before and many willing members here to help.

 

[basilbowman]

Brilliant - cheers. I changed the filter when I bought the truck a month ago, how much damage do you think I did, putting 1.5k miles on it? It wasn't shifting very hard, just out of first was a little clunky, other than that it wasn't bad, but it did feel limited as far as power goes up around 65, 70 on the freeway.

 

[icanfixall]

Its not really possible to say if you have done any damage at al. Drianing the fluid will tell you whats going on in the trans plus if it looks and smells burned you will know more. But from this side of the computer screen I really can't tell you one way or the other. A guess would be no damage but thats just a WAG at best.. If these computers had smell-o-vision we could tell you what the atf smells like.... But thats not going to happen round these parts.... Yet.... Do this... Remove the trans dip stick and wipe it off on a white tissue. See how it looks after it wets the paper for a few minutes. The oil will "travel" across the tissue and leave behind any trans clutch material if any is in the sample....

 

[OLDBULL8]

I don't even really know the part I need, it's a cylinder about three inches long with about a foot of wires coming off of it,

Whatever that is your referring too, it's not the tach sensor. The tach sensor looks like a 1" nut with two wires coming out of it with a connector on the end of the wires, screwed into the gear housing with the oil filler tube on it. See below.
Driving the truck without the tach sensor puts an E4OD into the limp mood, you only have 2nd and reverse gears, that is meant to be a safety feature just to get it out of the line of traffic not to drive it for any distance. The tach sensor, speedo sensor and TPS must work flawlessly for the transmission to work properly. Driving it that much, I'm sure you will have issues with the tranny down the road. That engine must sound like a screeming monkey and that is why your only getting 8-9 MPG. I would suggest that you change the fluid in the tranny after you get the tach sensor issue resolved, I'm quite sure it is more than likely burnt, after driving it that many miles without the sensor working.

C1016 is the tach sensor.

You must be registered for see images

 

[smolkin]

FWIW my WVO experiment resulted in slightly better mpg, but reduced power and IP problems as the WVO began to clean the fuel system and busted loose a bunch of crap that ended up in my IP. I strongly recommend a real aftermarket filter/ water seperator, as the OEM stuff didn't cut it for me. After a while on WVO you may reach the same conclusion I did; that it's far easier to improve the fuel quality than to make a rolling self-contained system to heat and filter the WVO on the truck. 1200 will get you an Ebay biodiesel processor or you can build one for much less. Otherwise you will be fixing stuff on the truck alot more often and if you're like me, a down truck=a down wallet.

 

[Shadetreemechanic]

I'm at home and have located my spare tach sensor. You are welcome to stop by and we can check it out.

 

[Blind Driver2]

FWIW my WVO experiment resulted in slightly better mpg, but reduced power and IP problems as the WVO began to clean the fuel system and busted loose a bunch of crap that ended up in my IP. I strongly recommend a real aftermarket filter/ water seperator, as the OEM stuff didn't cut it for me. After a while on WVO you may reach the same conclusion I did; that it's far easier to improve the fuel quality than to make a rolling self-contained system to heat and filter the WVO on the truck. 1200 will get you an Ebay biodiesel processor or you can build one for much less. Otherwise you will be fixing stuff on the truck alot more often and if you're like me, a down truck=a down wallet.

Was the straight wvo or bio? I'm thinking about going with straight wvo and maybe thinning it down with unleaded.

 

[h2odrx]

Was the straight wvo or bio? I'm thinking about going with straight wvo and maybe thinning it down with unleaded.

I would stay away from the unleaded, maybe diesel or atf or 2stroke?

 

[damac]

Was the straight wvo or bio? I'm thinking about going with straight wvo and maybe thinning it down with unleaded.

I did this as an experiment in my truck and an old vw jetta and i would say don't do it unless you can absolutely seperate the fuel systems and flush the wvo side to purge it all with diesel before shutdown!

Luckily I caught it early. It was a nasty ass experiment in the tanks and if allowed to sit in the filter and injection pump/injectors will make it hard to start soon and screw with the pump internals.

I broke down my vw pump after this experiment and long after what I thought was a good atf flushing and there was a buildup leftover in a few moving areas that created drag.

I also used a good dose of startron in my tanks right away after that experiment.

As far as how it ran, it was run down to less than 20 and seemed ok after the vehicles were fully warmed up, and even then I would only use it on long freeway runs or when they were working hard, get off the freeway switch to diesel.

My impression was the exhaust stunk bad, and engines seemed a bit smoother. Power perhaps down just a tad but other than that I had no impression that there was anything wrong in the operation of the engines.

 

[DeepRoots]

few thoughts:

1. Figure out what is wrong with the transmission. Tach sensor is needed. You are talking about another part we are unsure about.
2. go hang out with ShadeTreeMechanic, his posts have proven he knows what he's talking about.... he seems like a good fella, and you need someone with some experience regarding the 7.3's
3. Hold off on WVO until you have the truck running correctly. If the truck is running well, and you have a good feel for it, you will know when something is a little off. As it is now you could be causing a major problem and you would be unaware due to your unfamiliarity with these engines. I drove my truck for several years before I started running alternative fuels, it helped me work out the kinks in short order.
4. When I ran WVO, I advanced the timing a hair and it helped with power and mpg, but first see #3.
5. Fill out your signature (see mine below?) It is a lot easier for us to help you when we aren't guessing what kinda truck you have.
6. To get better help, please change your profile picture to something like: diesel smoke, your truck, an engine, or a pair of bouncing boobs. I'm more likely to look at your post if there isn't a Glam photo of a redneck Micheal Bolton looking at me.... it gives me the creeps (nothing personal, I just prefer bouncing boobs).

good luck!
Drew

 

[Shadetreemechanic]

I will be in the IH 1310 today at work. I will leave the tach sensor on the dash. Don't throw away your old one, as it may just need cleaning.
So for your last 1500 miles of driving was the OD light flashing?

 

[smolkin]

Was the straight wvo or bio? I'm thinking about going with straight wvo and maybe thinning it down with unleaded.

I agree with h2odrx; never mix in gasoline, I learned that the hard way with my friend's UHaul. I would only mix in another oil or an additive designed for diesel (I like DieselKleen). With the straight WVO I constantly had flow issues at higher RPMs, in addition to the IP problems, and after the HotFox pickup, VegTherm Mega, 30' of SAE 30R9 fuel line (WVO ate up all the 30R7), new IP and lift pump I had spent close to the price of a bio processor. In retrospect I should have just gone to bio in the first place.

Like DeepRoots said stay on pump diesel while ironing out mechanical issues, I try to reach a "diesel baseline" standard of running before I switch to bio.
Sorry about the minor derail, I just can't recommend bio over WVO enough.

fake edit: B100 exhaust smells great! It's like the midway at a fall carnival!