MSefi.com read only forum (Jan.15,2018)

Well, ive had my MS-II intalled and running my mitsubishi 6G72 3.0L v6 for over a year and over 10,000 miles. had a few hickups but for the most part its been quite reliable, even to the point of 30mpg highway driving.

however, ive recently run into a baffling issue that i can't seem to figure out and as the car is my DD it has caused me to be unable to go to work today. the initial issue started over the weekend where for some reason the car would run really rich and the only way i could keep it running was to either keep the throttle cracked or pop a vacuum line off and even then, instead of idling high at near 2000 like it should with the vacuum line off, it barely idled at 1000. it did this for a while and then stopped and ran fine. it did that twice over the weekend (900+ mile round trip) and yesterday did it again and hasn't "fixed" itself. What i did notice is that i believe it is tied to a voltage drop. Megatune was only seeing 10-11ish volts when the car was running (batt was at 14.xx volts measured at the terminals) also, i parked the car at the store for a minute and when i came out, the car started then died, the reason was that the relays were not tripping to provide power to the MS, fuel pump etc. I was able to get home buy hot-wiring the MS, FP and injectors and she ran like before, with the low voltage rich condition.

i haven't been able to figure out the issue, i tried to eliminate the relay board from the equation but the voltage drop is still there even though my source 12v wire i used to hotwire the car reads 12v, MT still only sees 11v at most. for wiring, i had the relay board on the inside passenger fender and the batt is on the drivers side. i had run switched 12 and constant 12v across the engine bay to the relay board with the occasional butt splice and some crimp wire taps for other 12v needs and the ground is only a short run to the aluminium motor mount (which is bolted to the iron block) and the batt ground to the motor connects to one of the aluminium heads.

im totally lost on this one and could really use some help. anyone have any ideas or advice? my plan at the moment is to re-wire the 12v, switched 12v and run teh ground to the same ground point as the battery to see if that helps.

Does the MS read voltage correctly on a Stim?

what voltage do you get at the input of the main voltage regulator on the MS board?
Do you see battery terminal voltage?

stim is MIA at home 3 states away and which regulator (inside the MS) are you referring to?

i re-did the grounds and now it sees 12v. i think part of the issue was i had the fan on switched 12v and that was pulling the voltage to the MS down low adding the fuel, in addition to an iffy ground.

im still stuck though as teh relays are not kicking so the MS only gets power if i hot wire it, same with the FP and injectors...i think something on my relay board gave out. Im going to see about getting a new board and just solder my connections straight to the board, no DB37, no butt connectors etc.

can low voltage to the injectors not to open and close correctly? i tried a new FPR and that didn't help, as far as i can tell its down to the injectors or the MS. I data logged it running which i can only do at part throttle and it bounces around a lot (see attached) either i fried the injectors or something else but i don't know what. i even added about 4 to the req fuel and it seemed to help a little but that might have been due to the partially open throttle and a vacuum line off (trying to get a high idle)