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Discussion Starter #1
My map sensor keeps going out.
I have my map sensor warranty and it runs great for a while and then my map sensor goes out again.
What could be causing this.
Thanks
 

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Discussion Starter #2
The map sensors or from O'Reillys.
I pull the codes and get error 22
The symptoms are either I get a high idol or really low idol if I press on the gas it'll want to die but when I replace it it runs perfect.
I have warranty need the map sensor so many times I'm just sick of it.
I just want to know why the map sensor keeps going out
Thanks
 

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yo C,
DTC 22 indicates the Manifold Absolute Pressure (MAP) sensor is out of Self-Test range. Correct MAP/BARO range of measurement is typically from 1.4 to 1.6 volts.
Do NOT use an ordinary voltmeter to check a Ford MAP sensor because doing so can damage the electronics inside the sensor. This type of sensor can only be diagnosed with a DVOM that displays frequency, or a scope or scan tool
Also make sure engine manifold vacuum is within specifications at idle. If vacuum is unusually low due to a vacuum leak, retarded ignition timing, an exhaust restriction (clogged converter), or an EGR leak (EGR valve not closing at idle).
A low intake vacuum reading or excessive backpressure in the exhaust system can trick the MAP sensor into indicating there is a load on the engine. This may result in a rich fuel condition.
A restriction in the air intake (such as a plugged air filter), on the other hand, may produce higher than normal vacuum readings. This would result in a load low indication from the MAP sensor and possibly a lean fuel condition.
Check the sensor's vacuum hose for kinks or leaks. Then use a hand-held vacuum pump to check the sensor itself for leaks. The sensor should hold vacuum. Any leakage calls for replacement.
"...The vacuum gauge should show 18-22 in-Hg @ idle, and maintain a steady needle. Rev it up to ~2500 rpm, hold it steady, and you should see the needle drop, then slowly increase to a level close to the idle reading (though slightly lower is normal)..."
Source: by SigEpBlue (Steve)

Possible causes:
circuit open between sensor vehicle harness connector and PCM.
circuit shorted to VREF, SIG RTN, or GND.
Damaged MAP sensor.
Vacuum trapped at MAP/BARO sensor.
Unusually high/low barometric pressure.
Kinked or obstructed vacuum lines (MAP).
Basic engine (valves, vacuum leaks, timing, EGR valve, etc.).
High atmospheric pressure.
Damaged PCM.
VREF circuit open at MAP sensor.
SIG RTN circuit open at MAP sensor.

The pinpoint test directs you to check the voltage to the MAP sensor. With the MAP sensor connected, use paper clips to back probe the MAP connector so you make contact with the terminals inside the connector by inserting the paper clips into the bak of the connector. This allows you to get voltage readings while the connector is plugged in. The other option is to use straight pins to pierce the insulation of the wires. First check the voltage of the outer two wires of the MAP connector by connecting a voltmeter to the clips or pins you have inserted. You should see 5 volts with the key on. This is the power to the sensor.

The BLK/WHTwire provides a ground called Signal Return (SIG RTN on EEC), it will show 0 volts with the black probe on negative battery terminal. The 5 volts VREF (ON EEC) (Reference Voltage) is supplied on the ORG/White wire. The Signal the computer reads is on the middle wire, DK BLUE/-Lt GRN (MAP on EEC). The correct MAP/BARO range of measurement is typically from 1.4 to 1.6 volts on the Signal (middle wire).

If any of the voltages are out of range, there is a wiring problem that needs to be tracked down and repaired. These three wires all go back to the computer. The signal wire (middle) is the only one not shared by other sensors, it goes straight to the computer. The Signal Return and VREF are also provided to other sensors

Wiring Diagram in a 90 5.0 & 5.8
http://www.supermotors.net/getfile/886851/thumbnail/1990-bronco-electronic-engine-control-243.jpg (http://www.supermotors.net/registry/media/886851_1)
Source: by Seattle FSB (SeattleFSB)


see my Vacuum Leak Test; @ [http://fullsizebronco.com/forum/showthread.php?t=206824&highlight=Vacuum+Leak+Test;+idling
 

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Discussion Starter #4
Thanks so much!!
I'll have some time this week to start testing i'll let you know how it goes.
 
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