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Quebecker
10-11-2012, 07:10 AM
Hi,

When I try to check the voltage of the sensor MAP during motor is at idle, the car seems to stop [engine semm misfire](he even already stopped) and I have a Check Engine Light P0107.

Under normal conditions, I never had the code P0107

MAP sensor reference voltage: 4.8 volts
MAP sensor reference voltage ar idle: 0.37 volts

Do you know what is the problem ?

Regards
Remi

Madsceintist
10-11-2012, 12:25 PM
This only happens when you test the voltage ?? or at other times?
If this only happens when your testing the voltage you are shorting a circuit that the computer needs for basic operation.
Make sure that your not back probing the leads and shorting them together or to anything metal. Also be very careful not to break the contacts inside the wire where as they have no contact. The wire insulation can be deceiving.

What it sounds like to me, is that you crossed the 2 leads for power and reference. In that sending a dead short the computer resulting in the code and stall.

Quebecker
10-11-2012, 02:01 PM
This only happens when you test the voltage ?? or at other times?
If this only happens when your testing the voltage you are shorting a circuit that the computer needs for basic operation.
Make sure that your not back probing the leads and shorting them together or to anything metal. Also be very careful not to break the contacts inside the wire where as they have no contact. The wire insulation can be deceiving.

What it sounds like to me, is that you crossed the 2 leads for power and reference. In that sending a dead short the computer resulting in the code and stall.

Only when testing voltage ...:confused:

myoldyourgold
10-11-2012, 02:40 PM
Exactly how are you hooking up your meter? By hooking it up in parallel and not interrupting the signal it should not effect the computer or the engine at all.

Quebecker
10-12-2012, 01:10 AM
Exactly how are you hooking up your meter? and not interrupting the signal it should not effect the computer or the engine at all.

Exactly, By hooking it up in parallel. It's very Weird

If I jump the reference voltage (4.8) to the signal voltage (4.8), I have the same behavior but this time, the CEL is P0108 (MAP sensor high voltage)

In normal condition, no problems with map sensor and no CEL

Madsceintist
10-12-2012, 08:07 PM
What poles are your meter on ?? I think your adding voltage to the circuit through your meter, or crossing your connection! :confused:

Quebecker
10-15-2012, 02:04 AM
What poles are your meter on ?? I think your adding voltage to the circuit through your meter, or crossing your connection! :confused:

I use the positive wire of the MAP and the negative on the chassis of the car

I will try a new voltmeter