When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
just curious. it's kinda pointless on these trucks because the mileage is so bad anyway, but it's cheap & i need a new weekend project. that and i got a fat empty spot above my stereo
for those who haven't heard of it, it's a little calculator for your mpg, it does instantaneous/trip/average/etc. hooks up to the vss, one injector lead, +/-, pretty basic stuff.
i'll keep this thread updated as i get everything hooked up if anyone else is interested.
requires a bunch of soldering, you can get a premade board or one you have to solder all the components on yourself, i was going to do the latter but put one of the resistors in the wrong spot and f'd the board removing it
new prebuilt one just came in yesterday, so hopefully by the end of the week i'll get the rest of the stuff put together and have it in.
yeah, you tap vss and an injector and using that it calculates your mpg. only need 4 connections to the car. the rest is just putting the damn thing together and tweaking the code to suit your vehicle.
got bored so i'm soldering stuff together right now board-wise, you've gotta put a couple resistors and diodes and crap in line w/ the connections and wire up the lcd to the circuit board.
did the grounds and buttons, will do the lcd tonight probably, then need to do the vehicle power and last couple diodes/resistors & tap the vss/injector. just gotta put together a mount out of plywood the size of my extra DIN above the stereo... then finally start tweaking the code.
This is a bit of a timelapse here, but @Recoil , do you have any good links for wiring instructions for one of these MPGuinos? I just bought two (very hard to find these days since basically all cars come with fuel info computers) and I'd love to wire one up to my 3VZE. Unfortunately I didn't pay very good attention when we played with Arduinos in computer science class in high school and that was 8 years ago. If anyone's got some advise it would be greatly appreciated
You don't need to know anything about Arduino's to hook up an MGPuino. As Recoil said, you only need to hook up four wires (B+, gnd, VSS1, and Inj).
If you don't care about super-high reliability, you can use plain-ole' solid conductor telephone wire. Back-probe the connector, then hold it in place with hot-melt glue.
You'll need to verify your ECM connections, but for me B+ B-G A1, gnd BR C11, VSS1 Gr A9, and Injector W-R C12
Wanting something less embarrassing, I eventually connected to the ECM a little more permanently. I depinned the connectors I wanted, carefully striped off about 1/4" of insulation, attached my MPGuino lead to the bare wire with a barrel crimp, covered it with heat shrink, then put the pin back into the connector. That's what I have now.
Appreciate the info, scope103. Also, follow-up question; does anyone know if an mpguino can be run entirely from the 3VZE OBD1 diagnostic port in the engine bay? I guess what I'm really asking is- is there a speed (VSS/SPD) signal terminal in the OBD1 port? I'm pretty sure the 3 other needed terminals are there. I'm still just a little hesitant to be permanently splicing wires directly to the ECU...
Four years? Well, I've got projects still hanging around from then.
There is no VSS signal on the OBD port. I'm 99.5% sure there is no Injector signal either, but you may know something I don't. Or you may not care about the factory INJ signal.
Lol I know right? I knew it had been a while but wow. Seems like that's all I've done is stockpile projects in my garage. Anyway, I know these mpguino units can't be pulling that many amps, but would it be overkill to install a fuse for it somehow? 2.5 amps? 5 amps?
If you don't care about super-high reliability, you can use plain-ole' solid conductor telephone wire.
So if I was worried about super-high reliability, what would you say would be the ideal wire choice to use for something like this? It's just that I have very little wiring experience and I want to eliminate any possibility of watching my car go up in flames from the side of the road
You don't need cat 6; this is a very low-speed signal (cat 6 sure won't hurt signal-wise, but it is difficult to work with). This 22ga 4-conductor is convenient to use. https://www.aliexpress.us/item/3256806229334531.html But if you already have some ethernet cable, sure, use it.
More important is the splicing. I described above how I replaced the phone wire; I used crimped barrels, covered with heat-shrink.