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Discussion Starter #1
If you are fortunate to have an OBDII Bronco (1996 only) then you can monitor real time fuel usage with a scangauge that plugs right into your OBDII port. The rest of us with fuel injection can get the same functionality from an MPGuino, but it takes a little extra wiring and calibration.

The MPGuino monitors the VSS signal and the pulse from any fuel injector, and uses this info to calculate speed, gallons per hour, instant fuel mileage, trip mileage, tank mileage, etc. The trick is calibrating the system to decipher the signals.

Installation

The MPGuino has 4 wires: VSS signal, Injector signal, 12v battery, and ground.




1. VSS signal

In my 95 I tapped into the red/pink wire under the steering column near the brake pedal.




2. Injector Signal

Each injector has 2 wires. They are different colors depending on if you have SEFI or bank fire injectors. SigEPBlue pointed out that you want the one that is NOT red. I tapped into the Tan/black wire.



3. Ground

I just used a self tapping screw and grounded to some sheet metal.



4. 12v Battery

You need 12v battery, not 12v switched. I happend to have 12v battery running to a switch in the cab for my strobes, so I just tapped into that. No pic taken since you will have to find another source. I suggest 12v that powers your stereo clock.

Calibration

There are 2 numbers to dial in to get accurate readings: VSSpulsepermile and microsecgallon.

VSSpulsepermile

This tells the MPGuino how fast your are going. This is critical and I'll tell you why.

I see some guys on here that say "I've got a 6" lift, 35" tires, and stock 3.55 gears on my 92 5.0 BKO and I get 24mpg." No they don't. I usually post or PM them and ask what their PSOM is set at and I never hear back.

If you have a 92-96 then you have a programable speedometer that needs to be adjusted when you change tire sizes. Steve83 did a writeup here If you have an older bronco then you need to change the speedo gear. Otherwise your mileage is off and you can't calculate fuel usage.

Same idea for the MPGuino. You have to get the VSS pulse per mile right so that your MPGuino shows the proper speed and miles driven. This varies by tire size.

I run BF Goodrich Long Trail 31x10.5x15 and have my PSOM programmed accurately. I set the VSS pulse per mile to 145645 and my MPGuino matches my speedometer and odometer. Today I drove past one of those radar signs and the sign, my speedo, and my MPGuino all said 30mph.

Making the adjustment is easy if you have different tires. Instructions are HERE

MicroSecGallon

This is the signal from the fuel injector. It is easy to calculate and easy to adjust as you get your device dialed in.

Bosch 19lb injectors for ford 5.0/5.8 flow 199.7cc/minute. Wagonman76 at Ecomodder developed an excel spreadsheet that crunched the microsecgallon constant for anyone who knows their cc/min flowrate.

The answer is 153191733. You may have to adjust this when you fillup. If your MPGuino fuel used does not match what you put in your tank, simply take Microsecgallons X Guino gallons / gallons pumped at the gas station. This will give you a new microsecgallons constant.

All hooked up

I still need to build an enclosure, so it is just sitting on my dash. Sorry for the crappy pic. You can see that I just got done with a 59 mile trip. I got 19.27 mpg, my speed and instant MPG is 0.000 since the truck is off.



Yesterday I drove 120 miles. In the morning I got 20.3 on the device and got 19.27 in the evening (as pictured). I filled up this morning and calculated 19.61 mpg based on 450+ miles driven and the amount of fuel pumped into the tank.

My Ride

I get pretty good gas mileage already, and now expect to beat my goal of a 20mpg tank with 31" tires. I have ported heads, a high lift cam, electric fan, synthetic fluids, kickass exhaust, Sixlitre tuneup, and I run locked out timing at 36 degrees.

Timing

I ditched my knock sensor after I did my cam/head swap bc it was always going off and retarding my timing. Then I read up on how mustang guys ditch the spout sometimes and run locked out timing. I have a few observations on it that go well with this thread.

At 87 octane I could run 26 degrees but got 15mpg per tank.
at 90 octane I could run 31 degrees but got 16.12 mpg per tank.
At 93 octane I can run 36 degrees and got 19.61 mpg on my last tank.

I don't want to encourage anyone to try this since you might blow your shit up, but it works for me. I have more responsive low end torque with this setup and really like it.

Observations

I have a few pages of observations on vacuum, rpm, driving style, speed, etc. I will post them tonight or tomorrow.

MPGuino links

Buy
Wiki (setup/usage instructions)
Forum

Continued . . .
 

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Discussion Starter #3
with all these modifiications and 87 octane fuel at 26 degrees timing you get 15 mpg?
26 total timing. That would actually be pretty retarded compared to stock. It would equate to 6 to 10 degrees btdc depending on which computer you have

+Rep! That's one thing this site needs lol. Great job on the write up.

It's not much to do with the topic, but I'm curious what that red thing is that you clip on the wire. Does it pick up pulses from the wire without tapping into it?
It's a wire tap I got from radio shack. It is 2 pieces. First wraps around the wire you want to tap into. You crimp your new wire into the 2nd piece and attach it to the first.
 

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so if im understanding this with these modifications and that much timing your only getting 15 mpg? it may be just me but sounds like somethings wrong. i can tell by your sig pic that you dont have the factory air dam but there must be something else dropping your mileage.oxygen sensor?:scratchhe i get 15 mpg in my 94 without the factory air dam and mud terrains. i also have a dirty filter, bad axle pivot bushings (just fixed) a never cleaned original 150000 mile engine,clogged egr, new o2 sensor (didnt let the car idle afterwards to get fuel trim settings.) and a crapload of extra parts in the back. unless im really conservative i dont see how your mileage can still be that low when youve done all that stuff.unless you have a lead foot, in which case that would be good mileage.:thumbup

oh yeah forgot to mention. if i did this id make a custom holder to hold it as well as my transmission temp gauge, put it next to that recess on the top center of the dash. i think it would look nice if you did it well. that location i think is best cause its right where you can easily see it but doesnt effect your veiw of the edges of the car, just a little bit of the hood. id use solder and heat shrink, put it in the factory wire loom or its own to make it look professional. if i ever sell it and decide i want to keep it i can just unplug the wire and tuck it in the defrost vent.
 

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oh yeah forgot to ask this too.:twak why do you have to have a 12 volt battery connection instead of a switched 12 volts? im guessing for memory. i just dont think id like leaving something like that on all the time even if it only uses a little power. i wonder if you could wire it to a 12 volt switched source and wire a rechargable 9 volt in line with it. that way when the power is switched off the 9 volt provides power to the memory but the screen stays off since there isnt enough power to it.

its great someone did w write up on this, ive searched google for hours and never found anyone who had done it.
 

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Discussion Starter #6
pfun, I don't think you understand that I'm talking about total timing, not base timing. Like I said, 26 degrees locked out total timing is more retarded than stock 10 degrees base timing. Thats why the mileage suffered. I could not run more than 26 locked on 87 octane bc under certain driving situations I would ping.

12v battery is necessary for memory, to calculate tank mileage. The device calculates instant, trip, and tank.
 

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pfun, I don't think you understand that I'm talking about total timing, not base timing. Like I said, 26 degrees locked out total timing is more retarded than stock 10 degrees base timing. Thats why the mileage suffered. I could not run more than 26 locked on 87 octane bc under certain driving situations I would ping.

12v battery is necessary for memory, to calculate tank mileage. The device calculates instant, trip, and tank.
im not understanding total. if i were to do base timing what would that be? why didnt wouldnt it work with more advanced timing? is it because the timing was locked out?
 

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Discussion Starter #8
Vacuum vs MPG vs gear

Vacuum

I could never get a straight answer on what was better, high vac or low RPM. The answer is: highest vacuum in highest gear.

In 3rd gear I can cruise with high vac and get 17mpg. In overdrive with lower vacuum I can cruise at 19 to 22, depending on grade/load. Once in overdrive, vacuum has a direct relationship to MPG.



As you can see mo vacuum is mo better. I have a vac gauge on my pillar that I always drive by.

Next opportunity I have to swap cams I'll try to find one for high vacuum. I wish I had left the stock cam in place. I love the one I have for romping on the gas, but it costs me at the pump.

Overdrive

At 45mph with 17" of vacuum, 3rd gear, 1900 rpm = 15mpg.
At 45mph with 17" of vacuum, Overdrive, 1400 rpm = 22mpg.

Acceleration

Accelerating from a dead stop sucks. 1st gear acceleration nets 2.5mpg!! 2nd gear gets 5mpg! Accelerating in 3rd approaches 10mpg, and in overdrive I can accelerate between 10 and 15mpg.

Don't Stop, keep moving, even if you are just crawling in 2nd it is better than having to stop and get the rig moving again.

Idle

Idling sucks bc you get 0MPG. In fact, you use 0.75 gallons of fuel per hour of idling. You can watch your trip/tank MPG slowly count down as you sit in traffic or at a light as you use fuel but don't add miles.

Pulse and Glide

This is where it is at. I've seen the ecomodders and hypermilers talk about this and now I'm a believer. Cruising on a level highway at 60 I can get 19-22 mpg depending on how high I can keep my vacuum. When I "glide" by letting off the gas, MPG ranges from 40 to 60mpg. "pulsing" around 60mph in overdrive gets 10 to 15mpg, usually 12. So if you pulse for 12 and glide for 50, both equal amounts of time, you can net 31mpg.

Even in choked traffic going 20mph, I was able to P&G today and stay around 17mpg.

Again, don't downshift when pulsing. Pulsing in 4th I can get around 12mpg. When I downshift to 3rd that drops to 7 to 9 mpg.


The problem with gliding in a bronco is that you may as well glide a barn. The P&G really helps keep the MPG up, but at 65 there is so much wind resistance that it is hard to glide more than pulse.

At 45 the BKO actually does a great job gliding. I can get better mileage in rush hour traffic due to this.

I suggest riding in the right hand lane on the highway if you want to pulse and glide. Lots of opportunity to coast due to merging traffic.

One annoying thing about P&G is waiting on the torque converter to lock when you hit the gas. RPMs rise fast then drop when TC locks. I wonder how much hit I'm producing by locking/unlocking so often. My temp gauge for the tranny filter is currently not working due to gremlins.

Air Conditioning - update 6/2/10

I charged my AC yesterday and used it for the first time this summer. Ice cold! The efan conversion is great because you can get ice cold AC at a dead stop in traffic with the Mark VIII fan blowing.

AC killed my normal commute mileage by more than 20%. I usually knock down 19.5mpg from job to driveway, and got 14.5 with the windows up and the AC on. I noticed the AC drops my vacuum by 2" also.

Running 65 down the road when I can usually read from 21 to 23 on the mpguino I had a hard time keeping it at 19. Low speed and city driving the hit was even worse.

Things that suck

Hills suck big time.
Stopping sucks worse.
Open loop sucks. You get bad mileage before the engine warms up.
Air conditioning

What's next for my Bronco?

1. I don't have a grill, just a big gaping hole in the front from breaking my header panel pulling the 5.0 out. I'm sure that is pretty damn aerodynamic. I could scoop up a homeless person into my radiator and not see him.

2. I'm going to do a grill block and seal up the hood and headlights. Anything that helps the truck glide longer will be great.

3. I'm contemplating a small belly pan like Pfun41 has been talking about

4. Alternator delete. Solar panels for the win.

5. Stock rear bumper is like a parachute. Take a look at yours, it is a big scoop behind the truck. I'm gonna rip it off and see what happens.

6. Make my own 110 octane ethanol at home. Drink half, advance total timing to 46 and run the other half through the bronco. Try not to blow anything up.

Now that I have an MPGuino I can really see which mods make a difference.

Questions

1. I know there is a mod for TC lockup. Would I want to manually lock the TC and then glide? Or would that just slow me down since the drivetrain would be connected to the engine.

2. I wonder if the EGR never opens since during P&G you are never crusing, just accelerating or idling. That's bad, since I love me some EGR gas to reduce emissions, displace cylinder volume, and cool cylinder temps.

3. Is there a way to lock my truck into overdrive. I keep accidentally downshifting and would like to stay in 4th to pulse.

Goals

Well, my original goal was a 20mpg tank with my BKO and 31" tires. I've had several high 19mpg tanks and a few 20mpg trips, so I think I'm there.

Now I want to see if I can pull off a 22mpg tank on 31s. I think I can do it.
 

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Discussion Starter #9
im not understanding total. if i were to do base timing what would that be? why didnt wouldnt it work with more advanced timing? is it because the timing was locked out?
stock base timing is 10 degrees and the computer adds 16 to 20 depending on the load, temp, rpm, etc. So 10+ 20 = 30. 10 is your base and 30 is your total. Advancing base timing to say 13 via six litre tuneup can net you 33 total timing.

Locked out timing means the computer can't control timing, so it is always the same. At high load and low RPM on 87 octane 26 was too high. The computer would have pulled some timing out and ran a little lower. However, at cruising speed with low load the computer may have wanted to run 30 to 40 degrees, but since it was locked out at 26 it was a dog and mileage suffered.

THE POINT IS: more timing is better for fuel efficiency, but you may have to run higher octane gas to prevent knock.

THE OTHER POINT IS that I'm not getting 15mpg. I have 36 degrees of total timing now and am getting 20+.
 

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stock base timing is 10 degrees and the computer adds 16 to 20 depending on the load, temp, rpm, etc. So 10+ 20 = 30. 10 is your base and 30 is your total. Advancing base timing to say 13 via six litre tuneup can net you 33 total timing.

Locked out timing means the computer can't control timing, so it is always the same. At high load and low RPM on 87 octane 26 was too high. The computer would have pulled some timing out and ran a little lower. However, at cruising speed with low load the computer may have wanted to run 30 to 40 degrees, but since it was locked out at 26 it was a dog and mileage suffered.

THE POINT IS: more timing is better for fuel efficiency, but you may have to run higher octane gas to prevent knock.

THE OTHER POINT IS that I'm not getting 15mpg. I have 36 degrees of total timing now and am getting 20+.

so the idea of locking out timing is to get more advanced timing in lower rpm range overall, while maybe scraficing a little timing on the top end of rpm range. makes sense seeing as people like us tipically stay in the low rpm range. i keep all my vehicles 2000 rpm or less. trailblazer is a bitch to do that with though, gm made it wait forever to shift and when it does shift it takes a long time to do that too, all for a little comfort. fuey
 

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Vacuum

I could never get a straight answer on what was better, high vac or low RPM. The answer is: highest vacuum in highest gear.

In 3rd gear I can cruise with high vac and get 17mpg. In overdrive with lower vacuum I can cruise at 19 to 22, depending on grade/load. Once in overdrive, vacuum has a direct relationship to MPG.



As you can see mo vacuum is mo better. I have a vac gauge on my pillar that I always drive by.

Next opportunity I have to swap cams I'll try to find one for high vacuum. I wish I had left the stock cam in place. I love the one I have for romping on the gas, but it costs me at the pump.

Acceleration

Accelerating from a dead stop sucks. 1st gear acceleration nets 2.5mpg!! 2nd gear gets 5mpg! Accelerating in 3rd approaches 10mpg, and in overdrive I can accelerate between 10 and 15mpg.

Don't Stop, keep moving, even if you are just crawling in 2nd it is better than having to stop and get the rig moving again.

Idle

Idling sucks bc you get 0MPG. In fact, you use 0.75 gallons of fuel per hour of idling. You can watch your trip/tank MPG slowly count down as you sit in traffic or at a light as you use fuel but don't add miles.

Pulse and Glide

This is where it is at. I've seen the ecomodders and hypermilers talk about this and now I'm a believer. Cruising on a level highway at 60 I can get 19-22 mpg depending on how high I can keep my vacuum. When I "glide" by letting off the gas, MPG ranges from 40 to 60mpg. "pulsing" around 60mph in overdrive gets 10 to 15mpg, usually 12. So if you pulse for 12 and glide for 50, both equal amounts of time, you can net 31mpg.

Even in choked traffic going 20mph, I was able to P&G today and stay around 17mpg.

Again, don't downshift when pulsing. Pulsing in 4th I can get around 12mpg. When I downshift to 3rd that drops to 7 to 9 mpg.


The problem with gliding in a bronco is that you may as well glide a barn. The P&G really helps keep the MPG up, but at 65 there is so much wind resistance that it is hard to glide more than pulse.

At 45 the BKO actually does a great job gliding. I can get better mileage in rush hour traffic due to this.

I suggest riding in the right hand lane on the highway if you want to pulse and glide. Lots of opportunity to coast due to merging traffic.

One annoying thing about P&G is waiting on the torque converter to lock when you hit the gas. RPMs rise fast then drop when TC locks. I wonder how much hit I'm producing by locking/unlocking so often. My temp gauge for the tranny filter is currently not working due to gremlins.

Things that suck

Hills suck big time.
Stopping sucks worse.
Open loop sucks. You get bad mileage before the engine warms up.

What's next for my Bronco?

1. I don't have a grill, just a big gaping hole in the front from breaking my header panel pulling the 5.0 out. I'm sure that is pretty damn aerodynamic. I could scoop up a homeless person into my radiator and not see him.

2. I'm going to do a grill block and seal up the hood and headlights. Anything that helps the truck glide longer will be great.

3. I'm contemplating a small belly pan like Pfun41 has been talking about

4. Alternator delete. Solar panels for the win.

5. Stock rear bumper is like a parachute. Take a look at yours, it is a big scoop behind the truck. I'm gonna rip it off and see what happens.

6. Make my own 110 octane ethanol at home. Drink half, advance total timing to 46 and run the other half through the bronco. Try not to blow anything up.

Now that I have an MPGuino I can really see which mods make a difference.

Questions

1. I know there is a mod for TC lockup. Would I want to manually lock the TC and then glide? Or would that just slow me down since the drivetrain would be connected to the engine.

2. I wonder if the EGR never opens since during P&G you are never crusing, just accelerating or idling. That's bad, since I love me some EGR gas to reduce emissions, displace cylinder volume, and cool cylinder temps.

3. Is there a way to lock my truck into overdrive. I keep accidentally downshifting and would like to stay in 4th to pulse.

Goals

Well, my original goal was a 20mpg tank with my BKO and 31" tires. I've had several high 19mpg tanks and a few 20mpg trips, so I think I'm there.

Now I want to see if I can pull off a 22mpg tank on 31s. I think I can do it.
i pulse and glide at this spot at school. pulse until i get to the top of this hill then glide to the next turn.

2: try tape over the big gaps. i was able to boost mpg from 17 to 21 with that and an electrc fan. (i was calculating wrong but the increase should be the same)

3: all or nothing! full belly pan will smooth airflow under the entire truck and give better off road performace, plus keep water aaway from sensative electronic parts. im actaully gonna fab a custom tcase skid to help airflow and clearence.

4: alternator delete FTW! best way i think is to just use a solar tender and charge a deep cycle battery at home at night.


5: belly pan will take care of that

6: thats not the only option. i heard you can dry algae, squeeze the oil out of it, and then refine that oil like normal crude. havent tried it, preoccupied.

questions:
1: it depends on your speed. at higher speed locking the tc will cause it to slow down cause of the engine resistance. at lower speed the engine will help the car along more when it otherwise wouldnt.

2:eek:pen it manually if you want to. just tap into the vacume solenoid controls.

3: i think i have an idea. you have the e40d right. why not disconnect the shift control signals coming from the computer. then the computer cant shift it. may throw a cel though.
 

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Nice.....I'm going to pick one of these up now....The vehicles I've had or have with them I find it pretty useful. Thanks for taking the leap....And you are getting some nice MPG numbers!
 

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Discussion Starter #14
2: try tape over the big gaps. i was able to boost mpg from 17 to 21 with that and an electrc fan. (i was calculating wrong but the increase should be the same)
This is what I'm talking about in the first post. If you don't calculate your mileage right then you don't know what your mileage is, and you shouldn't be telling everyone you got 21mpg. I will take your advice and fill the gaps and let you know how it works out.

Is your PSOM calibrated to your tires?

Interested in something like this for my super duty...You say they have OBD2 ones? Got a link?
Yes, read the first sentence in this thread. The word Scanguage is hyperlinked. Or you can google scangauge.

Nice.....I'm going to pick one of these up now....The vehicles I've had or have with them I find it pretty useful. Thanks for taking the leap....And you are getting some nice MPG numbers!
Thanks man. If you find a cool way to mount it take a pic.
 

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This is what I'm talking about in the first post. If you don't calculate your mileage right then you don't know what your mileage is, and you shouldn't be telling everyone you got 21mpg. I will take your advice and fill the gaps and let you know how it works out.

Is your PSOM calibrated to your tires?



Yes, read the first sentence in this thread. The word Scanguage is hyperlinked. Or you can google scangauge.



Thanks man. If you find a cool way to mount it take a pic.
:doh0715: Thanks
 

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This is what I'm talking about in the first post. If you don't calculate your mileage right then you don't know what your mileage is, and you shouldn't be telling everyone you got 21mpg. I will take your advice and fill the gaps and let you know how it works out.

Is your PSOM calibrated to your tires?



Yes, read the first sentence in this thread. The word Scanguage is hyperlinked. Or you can google scangauge.



Thanks man. If you find a cool way to mount it take a pic.
i dont know if the psom was ever calibrated. the po put 31" street tires on it, we had 32 in mud terrains put on it by 4 wheel parts and i dont know if they calibrated it. the thing is that if the tires are larger and the psom wasnt calibrated that means the car is going further than the speedo is reading. that means in theory i would get more mpg than im calculating cause i went firther than it says i did:thumbup. i know i didnt really get 21mpg, my point is that they were both calculated the same way so in theory the increase with those mods would still be the same.
 

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Just curious about the vacuum. Where is the best place to plug a gauge into? I have a couple of capped off points on the intake manifold on my 92 EFI 6cyl. I was thinking about getting an a pillar gauge pod and a vacuum gauge was one of the reasons for it.


P.S. Thanks for the writeup. I'm waiting on mine to come in. I ordered it a few days ago.
 

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Discussion Starter #18
Just curious about the vacuum. Where is the best place to plug a gauge into? I have a couple of capped off points on the intake manifold on my 92 EFI 6cyl. I was thinking about getting an a pillar gauge pod and a vacuum gauge was one of the reasons for it.


P.S. Thanks for the writeup. I'm waiting on mine to come in. I ordered it a few days ago.
I run my vac gauge to the manifold tree and am happy with it. I definately like the pillar gauge setup. I have a 2 pod pillar and wish I had 3.

I ran a switch to the temp gauge in the pillar and can switch between tranny and engine temp, since the senders are the same.
 

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That's cool I think I have 2 or 3 capped points on my tree. Just curious, how much vacuum do you pull with setup? I checked mine with my Mighty Vac when I was trying to track down any leaks ans I was getting pretty steady 20in/Hg throughout.
 

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Discussion Starter #20
That's cool I think I have 2 or 3 capped points on my tree. Just curious, how much vacuum do you pull with setup? I checked mine with my Mighty Vac when I was trying to track down any leaks ans I was getting pretty steady 20in/Hg throughout.
I pull 18 at idle in drive, and 20" idle in neutral. My current cam has less vacuum than stock though. You could do better.
 
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