August 13, 20169 yr I know a few folks have dabbled with this but it does not seem to be well documented. I'll build this into a write up Once i get up and running. I Got my Microsquirt wired in. I'm starting with ignition only. Ford EDIS with VR sensor on Crank. I used power from the coil to close a new relay for the EDIS and Megasquirt. (black-white) I spliced together the Yellow Tack wire (subaru) to the Green Tack output from Microsquirt. The yellow wire used to come from dizzy and and go to the ECU and Tack. Fuel pump does come on. My tach bounces while cranking but I am NOT getting the injectors to open. Tuner Studio also sees the crank spinning. Battery is charged to 14v. While cranking the timing light shows 7* advance. (not perfect but close) Any ideas on why I'm not getting fuel? There is an extra grey wire that used to be connected to my coil. It is not in my wire diagram. Does it need to be grounded? Thanks!!!! Photos coming soon!
August 13, 20169 yr Author Here is the wire diagram, I am using. Modifications are written in in pencil near the ignition coil. Wire Modifications to the Subie Harness at the old coil location. Including the mystery Grey wire with loop. Edited August 13, 20169 yr by coronan
August 13, 20169 yr Subscribing for future project. I'll take a look under my hood tomorrow and see if I can find that grey wire in mine. I have an 84 turbo coupe, so it should be very similar. Your wiring diagram picture isn't showing up on my end, the others are working though.
August 14, 20169 yr It's working now. Looks like the Hayes manual ecu diagram. I have a scanned copy of of the ecu diagram from the 84 Subaru fsm that might be of help. I'm not sure how well the quality will be because it was shared with me on Facebook, and it's know for killing picture quality.
August 14, 20169 yr So reading your post and looking at what you did, it appears you left the yellow wire from the dizzy to the ECU intact and just back tapped it with the MS tach output. If so, I'm pretty sure you can't do it that way. The MS circuit is going to mess with your output from the dizzy, and that's what controls the injectors via the ECU. Older system dizzy outputs are higher current, analog while newer systems use a digital, low current signal and using both on the same circuit is not compatible. I suspect the MS is interfering with the signal from the dizzy. There's really no need to use the tach output from the MS since the dizzy supplies the tach output to the car.
August 14, 20169 yr Author Keen eye skishop! I have actually tried 2 different wire configurations. MS tach output to yellow (ECU + Tach) and the 3 way splice. (Dizzy output + MS tach output to ECU + Tack input) That makes sense with the difference in signal coming from the dizzy vs MS. Next I will try clipping the MS tack output and just feed the ECU with the Dizzy. Bratman: I chose Microsquirt V3. It looked like the best bang for the buck. Thanks for the diagram but i cant read the wire colors.
August 19, 20169 yr Author Photo dump. Check back for descriptions. Ford Edis control module I used a fuse as a means for a jumper. The module can run independent from the micro squirt when the jumper is removed. Mega squirt has info on their site of where to get parts at pick and pull or new. Crank wheel came from 98 Ford ranger. easy machining on the lathe the make it fit the Subaru crank pulley. Of i has to do it again, I might buy the wheel from DIY auto tune. Mounting the sensor is tricky. The only bolts near the crank pulley are the oil pump, and those need to seal. So I bolted to the large bolt on the head and on oil pan. Mixed and matched to save money. I got some parts from DIY auto tune,. Rock auto and pick and pull. I'm in for about $600 Edited August 19, 20169 yr by coronan
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now