blkyata

Hello, I am having issues with my Ms3pro pnp for my NB 2000 miata. The issues are with voltage, I have been trying to chase down a voltage “leak” i was having, where my megasquirt would read less voltage than my battery and it wouldn’t start under own power. Well, I have taken it to multiple shops, all say I have no issues. What I checked now is my battery, Alternator, and my ECU harness output. They all read the same, I told mt tuner this, he recalibrated the ecu, had it running fine. I told him i’d go out for a drive later, great. Started the car later to go out, turned on fine no problem, when i stopped to where i was going and shut the car off, came back to it later and I was having the issue again, the car would not start. I checked my tuner studio and it read 12.2-12.3, checked my battery and it was at the 12.5-12.6 area, still no start, and the calibration was off again. My tuner said its probably my ecu, I’m really at a loss now, I don’t know what to do, I’ve been having this problem for a few weeks and this car is my daily driver so I can’t even use it. My battery and alternator work fine, they’re new, I will attach my tune file and a data log where this happened today, my tuner is telling me i have a bad wire somewhere or that I could try a new starter/bigger battery as the cranking is too low. Any other people had issues like this? Any help appreciated.

Tune File:
https://fastupload.io/RaWULpyzAChc9BU/file

Data log:
https://fastupload.io/kduZuIfHhzvR7SP/file

Ted75zcar

iTrader: (2)

high speed log (SD) while starting with the jumper cables
high speed log (SD) while not starting with the battery
look at the cranking RPM difference between the two
look at the voltage difference between the two
adjust the tune cranking RPM accordingly

blkyata

Hi, my tuner said that “cranking rpm won’t affect your voltage in any manner”.

Ted75zcar

iTrader: (2)

Your cranking speed is voltage dependent. Cranking rpm is the speed where the ecu transitions from crank to run.

There are other things going on there that you need to see to understand why it is or isn't starting. This is tuning 101.

Ask your tuner how many standalone from scratch builds he has done with flex and 0 degree F cold starts.

blkyata

My tuner has done a couple hundred cars from what I see all the good reviews he has, I just put in a higher CCA battery (650), and it still wont start. It will start under a battery charger, but isnt starting under its own power. Weird thing is, if I let the car sit for a while/all day, and try to start it, it'll start up on its own power at the 350 cranking rpm i have it at. I did happen to lower the cranking rpm to 200, it sputtered a bit but it does start under its own power at 200 when warm/not sitting all day.