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Asked by: Alami Isenborths
automotive auto partsWhat PSI should a MAP sensor read?
Last Updated: 24th April, 2020
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Also question is, what should map Psi be at idle?
In pounds per square inch, the atmosphere exerts 14.7 PSI at sea level on average. The vacuum inside an engine's intake manifold, by comparison, can range from zero up to 22 inches Hg or more depending on operating conditions. Vacuum at idle is always high and typically ranges from 16 to 20 inches Hg in most vehicles.
Additionally, what is normal intake manifold pressure? An average intake manifold pressure around -700 mbar (i.e. a vacuum, relative to atmospheric pressure). A series of small depressions, producing a ripple effect, cycling at around 21-25 depressions per second. The depressions are equal in amplitude (around 10 to 15 mbar).
Regarding this, what should map be at idle?
Normal idle should be steady with no more than a 50 RPM variation. This was the first clue. The MAP voltage readings should range between 0.9 to 1.5 volts. This vehicle is high at times, indicating pressure pulses in the intake.
How do I know if my map sensor is bad?
Signs of a Broken MAP Sensor
- Poor Fuel Economy. If the ECM is reading low or no vacuum, it assumes the engine is at high load, so it dumps in more fuel and advances spark timing.
- Lack of Power.
- Failed Emissions Inspection.
- Rough Idle.
- Hard Starting.
- Hesitation or Stalling.
- Check Engine Light.