My CEL came on the other day randomly showing a code 3 MAP Sensor. So the first thing I did was check for any vacuum leaks, and for any frayed wires going into/out of the map sensor.

I didn't notice anything, and assumed it was just the MAP sensor itself, and purchased a new MAP senor. After hooking it up, I was still getting the code 3. I then took out the voltometer, and hooked it up to the YEL/RED wire and the ground and was getting a reading of 3.0 volts. So I knew something was up with the wire going to the plug.

I decided to make a small incision pre plug on the wire to test voltage before it go to the plug, and I was making 4.5 volts, so I then assumed something had to be bad within the plug itself. So, I fiddled around with the wire going into the plug a bit, when I started getting a reading of 4.5 out of the plug now.

I decide to hook it up and reset the ECU hoping that my fiddling had fixed the problem. Of course, after I started the car, I still got the code 3 and usual idle issues.

So, I went again to test the voltage and was getting 3.3 volts now both at the plug AND before the plug in the incision I had made earlier.

All the manual says to do is replace the ECU :/ I haven't gotten around to testing the volts at the ECU itself, but that's what I'm going to do next. Just wondering if anybody has any ideas as of what it can be, or other little things I can do to test it out to get my car running normal again. Thanks in advance.

 

Bump for a dude that needs some ideas

 

Turns out my battery was just so weak that it didn't have enough juice to send 5 volts to the ecu Replaced, and everything is running fine