My car mysteriously stalled today while driving and I found the boost reading on the PFC stuck at 1.2bar even with the engine off. It still read that way when I unplugged the MAP sensor. That false reading probably ran the engine super-rich...stalling it out.

I *believe* the issue was due to a shotty S-AFC install that someone else performed a few years ago. I think the wiring wasn't quite so secure as a jiggle of the pigtails cause the boost readings to fall back to normal. I have since uninstalled it (since I don't use it anymore) and repaired the wires.

Long story short, I was wondering: would a broken/bad/grounded connection to the ECU MAP sensor wire cause a false reading of 1.2bar for safety? I just want to make sure that I've solved the issue and that the problem isn't something else.

Thanks in advance.

 

Your map signal wire would have had to short to power to get 1.2bar. Our stock maps max out at about 1.2-1.3 bar, with a corresponding map output value of 5v (reference value). It wont read anything higher than that regardless of input voltage due to pcm limiting it at 5v due to that being the reference value. I dont think its a saftey thing, more of just a your sensor got shorted type of thing.

Dan.

btw what did you end up pulling after steve kan was done?

 

with the sensor uplugged though the reading would be 0 volts so it looks like your signal wire is grounding with your 5 volt reference wire from the ECU.