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MAP Sensor Voltage Too High

Name of Code:
MAP Sensor Voltage Too High

When Monitored:
With engine rpm above 400 but less than 1,500 and closed throttle.

Set Condition:
The MAP sensor signal voltage is greater than 4.6.

Theory of Operation:
This sensor measures manifold absolute pressure and ambient barometric pressure within the manifold. It provides a 0 to 5-volt signal to PCM cavity 36. The MAP sensor puts out a low voltage signal (0.5 to 1.8 volts) at idle when the manifold vacuum is high, and a higher voltage signal (3.9 to 4.8 volts) at deep throttle when the manifold vacuum is low. The MAP receives a 5-volt supply from PCM cavity 61; voltage may vary from 4.8 to 5.1 volts. The sensor ground is provided by PCM cavity 43.

Possible Causes:
- Signal circuit open
- Malfunctioning MAP
- Sensor ground circuit
- Sensor signal circuit shorted to voltage
- PCM failure
- Connector terminals
- Connector wires