Plugged in the MS3 for a temp time to try it out. Found it didn't work right off the bat..


When I started this, I made a spreadsheet to show which wire of the factory plug/harness went to each wire of the MegaSquirt/MegaSquirt3x harnesses.


The first issue I ran into was getting the correct reading from my crank sensor. After figuring out the crank sensor wiring of the harness I got which was different than others usually wire these in vw's, I was able to get some signal input. There was still a problem with it but it wasn't too bad of an issue once we started to work it out. Everyone I know of running the MS on their VW has the crank sensor set to falling edge. This is in relation to the sensor counting the teeth on the crank sensor wheel. In the following pic you can see two long teeth (One really long and one semi.. About half of the really long one) which indicates that I needed to change the MS3 to change the software to look at the raising edge rather than the falling edge.


Once that was resolved, the motor fired right up however the idle was wandering but I had not yet set that up in the software. I quickly set the tune to control the idle and realized I need to either modify my MS3 by adding a TIP120 and a diode into the PWM FIDLE (Idle) circuit or switch over to using the Idle output on the MS3x. The current plan is to switch over to the MS3x Idle output and give that a shot tuning the MS to use PWM Warmup Only output to control the Idle valve. With the generation of my car, the MS3x output is hit or miss whether it will just work or not so I need to test it and if it does not work then I will mod the FIDLE circuit and switch back to using that. Either way I can resolve it and that is next step. Following the Idle will be some tunning on the NA motor and then I move to building the new motor setup followed by the turbo setup