Hello all. Have a 99 Accord with the 3.0. **** ton of miles. Have this issue where the idle fluctuates from 12-1800 rpm in park/neutral, acts normal in gear. Read the P0108 code. If I unplug the MAP while it's running, it stops surging and idles fine, so I know it lies within that system. Now, I read around best I could and noted that I should have 5V BETWEEN the two outside wires. Or, In other words, I should have 5V from one of the wires to known ground, and 0V ( continuity) from the other to ground. WELL, I don't. One wire is right at 4.99V to ground (battery negative), but the other is reading around 4.5-4.6V. SO, my question is, A) what could cause this, B) is there something to check that could illeviate it, C) If I straight up ground the one wire, if it came to it, would any issues come of it? Thanks all for the help. I found info in trouble shooting, but none on addressing actual wiring problems. Thanks.

 

any help?

 

need to get this figured out

 

The car is reading too much air past the throttle plate, then it drops the idle then noticing the lack of air pressure behind the plate and raises the idle, repeat, repeat Ultimately sounds like a vacuum leak. This example being in normal situations, considering you're getting the P0108 code I would honestly just replace the MAP sensor.

 

I understand what's happening, and where the problem lies. However, in the little bit of info I WAS able to find, people definitively said you should have 5 volts between the outer wires regardless of sensor. And I don't. My "ground" wire reads 4.66V to ground.

 

The leads aren't corroded at all?

 

battery leads all look fine and are tight. wires leading to the plug aren't torn, corroded, etc.