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

I have a ms2 v3 and want to use it as an extra injector controller on my 99 Saturn. Problem I have is I hook up the trigger wire on the tach wire I lose my dash tach. if I hook it up on the white trigger wire for coil 1 and 4 at coil it shorts circuit and have a bad miss. is their some way I can get a tach signal for the ms2.

If I'm not mistaken, the Saturn (and other Chryslers of that era) were CDI, and you can't use coil negative sensing with CDI. If you hooked into the power feed wire, you may have damaged your MS.

I used the same wire I used for my auto meter tach. my car has 2 coil packs that are on a module. their is a tach out "from my pcm" that goes to my dash tach and it is like a 6 ppr. if I hook the ms2 to that I loose my tach. on my ign module has 2 different sense wires on to tell the 1/4 coil to fire and 2/3 to fire. 1/4 is white and 2/3 is orange "Both are 1 ppr". if hook the ms2 to white I get a real bad miss like not hitting at all on 2 cylinders and the same thing happens if I go on the orange. I don't think I hurt the ms2 because it used to run the car with an obd1 ign module and was hooked up very similar. it seems like the ms2 is distorting or pulling down the signal to bad for the stock parts to understand the signal anymore.

You may be able to trigger the MS2 off the crank wire instead, or see if the VR circuit doesn't interfere with the tach.

I think I am using the vr circuit. I bought the years ago and it was pre wired from DIYAutoTune. It has a shielded wire to pick up a signal. It was hooked uo to the tach mire on the obd1 system and worked fine. I dont want to run full stand alone nemore. So wired the stock stuff back up and now im stuck. I dont understand why I can hook up a tach to the wire with no problems but the ms2 will kill the signal.

If you are running the Hall / optical circuit, it could be pulling the signal to ground.

Im not to sure what circuit I am using. I thought it was a vr but not sure. The number on the unit is ms230-c. Hope this can help. I told you guys what I was gona do with them and bought 2 if them with innovate WB and hooked them up and they worked. Internally I have no clue on how they work not to mention that the car has been parked for 3-4 years.

You'll need to open up the ECU and see if TachSelect (in the lower right hand corner of the board) is wired to VRIN or OptoIn.

well it is set to optical in. before I change this I just wanted to make sure that hooking it up this way will be able to take 5 volt signal from the coil module to trigger it and not damage the ms2.