MPGuino issues - Fuel Economy, Hypermiling, EcoModding News and Forum

Johnny Mullet · 12-13-2009, 11:10 PM

I just got done installing my MPGuino in the wife's 1997 Metro. I got a constant power source, a solid ground, tapped into the ECU for the vss and the injector wire. It booted up and I went through the setup. As soon as I started driving, the MPGuino began flashing rapidly until I get above 40 MPH and then goes blank. When I reduce speed it comes back on, but flashing rapidly (like vss or inj signal flashes) and when I come to a stop is stops flashing and reboots?

dcb · 12-14-2009, 12:04 AM

I think some wires must be crossed, I know that plug is frustratingly small. It tested ok on the bench, not too likely it got messed up in that maner in transit.

can you trace your taps to the labled connectors (batt, gnd, inj,vss)

It might need a reflash if it was being powered from the vss on accident),

note: you can lift the plastic tang on the plug gently with an exacto knife and slide the pin socket out if you want to try it with the vss disconnected or need to shuffle pins around.

Do you know if you got a gph reading before you started driving (GH)?

Johnny Mullet · 12-14-2009, 12:09 AM

I will double check the wires tomorrow. When first boot happened, it did have a gh reading.

CoastRider · 12-14-2009, 01:49 AM

Mine did that on the first run. went straight to the batt for power and better solder job cleared it up.

Where can I get a new plug? or just new terminals My solder skills were a bit rusty, I checked radio shack but no luck.

dcb · 12-14-2009, 08:12 AM

It is the same plug is used to power a 3.5" floppy. If you have a desktop computer you probably have a spare inside there that you can cut out with a bit of pigtail. (turn off power first)

Johnny Mullet · 12-14-2009, 11:41 AM

Quote:

Originally Posted by dcb

It is the same plug is used to power a 3.5" floppy. If you have a desktop computer you probably have a spare inside there that you can cut out with a bit of pigtail. (turn off power first)

I just went into the closet and stripped the plug from my old eMachines eTower 667

Much easier this time around to wire it in. Can't wait for the wife to get home so I can finish it. I will update.

Johnny Mullet · 12-15-2009, 09:22 PM

Well, I finally got around to finishing the MPGuino project. I had a few wires backwards making the initial problems I had. This must be a well built device since I had the positive switched with the Injector pulse making the thing flash with great intensity. I brought Blue Jay into Mullet's Redneck Repair Shop.............

Using the instructions found HERE I tapped into the fuel injector first..........

And then to the VSS wire at the ECU here........

I took it for a nice ride, but it was snowing and we had a couple inches on the ground, so I could not get the full experiment out of it, but it works well! I may just have to get one installed in my Metro now.

Just a tip. If you sell these with a pre-made plug with a foot of wire for each terminal, this would take a lot of frustration out of installing it.