Map sensor not picking up boost 2011 5.3
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Map sensor not picking up boost 2011 5.3 The car reads the MAP sensor fine when key is on and when engine is running and under load, it doesn't see boost on MAP sensor. I can put air to the sensor and it will read perfectly fine I've put 22 psi to the MAP sensorand it reads. Once it's under load street or dyno it won't read above 1.5-2.5psi on MAP even tho analog manual gauge next to it shows 6.0-6.5psi
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Joined: Jul 2022
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From: Alaska
MAP sensor has three pins.
0 Volt reference ( ground)
5 Volt reference ( from PCM)
Signal, range about .5 to 4.5 volts, generated inside the MAP sensor, in linear response to Pressure.
Probe the wires while engine is running, figure out which voltage is MISSING.
Either you have a bad ground ( probably passenger side, BACK of engine, up high close to oil press sender)
OR you've got something pulling your 5 Volt reference voltage DOWN: Could be another sensor on the same 5 volt buss, or loose pin in PCM, or a wire rubbed/chafed..
. Point is, it's one of the THREE wires: stick a pin in there, and check voltages.
Report back what ya find .
0 Volt reference ( ground)
5 Volt reference ( from PCM)
Signal, range about .5 to 4.5 volts, generated inside the MAP sensor, in linear response to Pressure.
Probe the wires while engine is running, figure out which voltage is MISSING.
Either you have a bad ground ( probably passenger side, BACK of engine, up high close to oil press sender)
OR you've got something pulling your 5 Volt reference voltage DOWN: Could be another sensor on the same 5 volt buss, or loose pin in PCM, or a wire rubbed/chafed..
. Point is, it's one of the THREE wires: stick a pin in there, and check voltages.
Report back what ya find .
10 Second Club
Joined: Nov 2005
Posts: 933
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What MAP sensor?
If it is not stock, did you change the Linear and Offset in the tune?
Where are you getting a reading of 20psi when you blow air inti the map sensor?
Can you pos t a HPTuners tune file and log?
If it is not stock, did you change the Linear and Offset in the tune?
Where are you getting a reading of 20psi when you blow air inti the map sensor?
Can you pos t a HPTuners tune file and log?
I don't know about that particular year of PCM or what OS you are using.
On the 411's, you have to select MAP - 2bar in the scanner. Even though you change the offset in the tune, in the scanner it won't read above 105kpa with the generic SAE MAP sensor PID
On the 411's, you have to select MAP - 2bar in the scanner. Even though you change the offset in the tune, in the scanner it won't read above 105kpa with the generic SAE MAP sensor PID
