Stuck in Limp Mode, Code 14

[tec_41]

One night this happened when I was just cruising around...The car lost all power, started to sputter, died, and when I started it again it could barely idle (wants to die) and was limited to about 3800rpm. I shut it down, started again, and got it home just fine- No check engine lights, ran like it should.

This happened again on the highway with my cruise control set yesterday. This time it was stuck in limp mode, and still is. It sounds like launch control when I try to free rev it, and it runs pretty poorly. I threw a Code 14, which says the Map sensor voltage is too high or low. I replaced the sensor, no luck. I had a spare ECU and replaced that for the heck of it, no luck. Checked for melted wires by the ECU, nothing.

I'm gonna go outside and try to take a reading with a voltmeter in a few minutes, but if you guys have any ideas I'd appreciate it. Hopefully this won't be too much of a time waster...


EDIT: 4.95v on one pin, .1v on another, 0v on the third...What should they be at?

 

[tec_41]

I tried something interesting...Instead of taking voltage readings from the MAP plug, I tried using each of the 3 pins on the plug as a ground and put the voltmeter on my battery.

Two out of the 3 pins worked as a ground! So I was thinking this could possibly mean they are melted together somewhere or are maybe touching some metal. Thoughts?

EDIT: Figured it out myself...

 

[VelocitàPaola]

I tried something interesting...Instead of taking voltage readings from the MAP plug, I tried using each of the 3 pins on the plug as a ground and put the voltmeter on my battery.

Two out of the 3 pins worked as a ground! So I was thinking this could possibly mean they are melted together somewhere or are maybe touching some metal. Thoughts?

Got it myself...

All that means is that two of the three pins have low input impedance. I don't mean to sound condescending, but don't do that again if you care about your car... you can very easily damage electrical components by doing what you did.

Sensors like MAP sensors have a power, ground, and signal wires. My guess is that the +4.95V wire is for power, the 0V wire is for ground and the other is for the signal. If you have the sensor connected and measure the voltage on this signal wire, it should vary with the pressure inside the manifold.