1992 Mustang Lx Wont Run

To prevent the replacement of good components, be aware that the following non-EEC areas may be at fault:

*Unusually high/low barometric pressure.
*Kinked or obstructed vacuum lines (MAP).
*Basic engine (valves, vacuum leaks, timing, EGR valve, etc.).

The Manifold Absolute Pressure (MAP) sensor operates as a piezoelectric (pressure-sensing) disc. However, rather than generating a voltage, its output is a frequency change. The sensor changes frequency relative to intake manifold vacuum. The sensor frequency increases as vacuum increases. The MAP sensor allows the PCM to determine what the engine load is. Its signal affects air/fuel ratio, ignition timing, EGR flow and altitude compensation.

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Symptoms of a BAD MAP Sensor

When the Manifold Absolute Pressure (MAP) Sensor goes BAD, you'll get a failed MAP Sensor Diagnostic Trouble Code.
You'll see one of the following Trouble Codes:
Code 22: MAP Sensor out of range.
Code 72: Insufficient MAP change during Dynamic Response Test.
Code 126: MAP/BARO Sensor higher or lower than normal.
Code 128: MAP Sensor vacuum hose damaged or disconnected.
Code 129: Insufficient MAP change during dynamic response test KOER.

You'll also experience:

Engine cranks for a long time before it starts.
When the Engine starts, you get a lot of black smoke coming out of the tail-pipe.
Engine stalls as soon as it starts.
If the Engine stays running, it idles very rough.
If the Engine runs, you'll get really bad gas mileage.

The Manifold Absolute Pressure (MAP) Sensor is one of the most critical sensors the PCM (Powertrain Control Module = Fuel Injection Computer) needs to give the Engine in your car, pickup, van or SUV running optimally and so, when the MAP Sensor fails... you'll get some hard symptoms.

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