I assume we have a 2-3 bar map sensor. Can someone point it out for me? I'm needing it as a water/meth injection input.

Top driver's side of engine, in deep. Better go for the harness to hook up.

Strange, I looked through my SI, I couldn't find one.

does it have a different name?

does it have a different name?

Yes, boost pressure sensor.

Drats, I found it and wanted to post this before you did. Thanks Fingers

"The boost pressure sensor measures the pressure inside the intake manifold. Pressure in the intake manifold is affected by turbocharger output, engine speed, accelerator pedal input, air temperature, and barometric pressure (BARO). A diaphragm within the boost pressure sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The sensor translates this action into electrical resistance. The boost pressure sensor wiring includes 3 circuits. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5-volt reference circuit. The ECM supplies a ground on a low reference circuit. The boost pressure sensor provides a signal voltage to the ECM, relative to the pressure changes, on the boost pressure sensor signal circuit. The ECM converts the signal voltage input to a pressure value.
Under normal operation the lowest pressure that can exist in the intake manifold is equal to the BARO. This occurs when the vehicle is operating at idle or when the ignition is on, while the engine if off. Under these conditions the ECM uses the boost pressure sensor to aid in diagnosis of the BARO sensor. The highest manifold pressures occur when the turbocharger output is high. Manifold pressure can range from 58 kPa (8 psi) when pressure are low, to more than 240 kPa (34 psi) when pressures are high, depending on the BARO. The boost pressure sensor has a range of 33-255 kPa (4-36 psi). The ECM also uses the boost pressure sensor to provide engine overboost protection. The ECM monitors the boost pressure sensor signal for pressure outside of the normal range. If the ECM detects a boost pressure sensor signal pressure that is excessively low, DTC P0237 sets."

My question based off the information is

"it says the boost pressure sensor has a range of 4-36 psi. Most 3 bar maps only go up to 29.4 psi. Is this one different in the fact that it reads higher? If so, I'm going to the dealer tomorrow to pick up one of these for my boost control and for the LP system as the my data graphs max out at 30. When reviewing a pass, it's all flat line if the boost is above 30 psi.

Guess I could test it to find if it does read that high by tapping into the output signal but if someone could confirm this, it be much appreciated.

Thanks in advance.

Why would you get another one? Just tap the one in there.

The sensor is an absolute 3 bar. Thats about -10 to 30 PSI above MSL pessure. There are actually two on the engine. One Baro pressure sensor to measure ambient air pressure and another the absolute boost. Boost is actually the latter minus the former.

5 volt output? so 0 volt is -10 psi, 5 volt=30psi??

I still have found it under the hood, buried, if anyone knows where the leads are, please describe, I'll get the multimeter.

Mine (LB7) is located just to the right of the IAT. In the elbow right before it goes into the engine. Has a little hose that goes straight down to a nipple on the elbow.

So just to verify, the sensor on the truck is a typical 3 bar map, therefore no reading above 29.4?

Looking for something to read up to 40 psi minimum without speding the high dollar for a 5 bar sensor. Chances are I will be azz'ed out.

Do I have to do everything for you boy!!

First pic has the Boost sensor connector circled.

Mine (LB7) is located just to the right of the IAT. In the elbow right before it goes into the engine. Has a little hose that goes straight down to a nipple on the elbow.

That is correct, and my pics were for a LLY.


So just to verify, the sensor on the truck is a typical 3 bar map, therefore no reading above 29.4?
That is also correct.

Looking for something to read up to 40 psi minimum without speding the high dollar for a 5 bar sensor. Chances are I will be azz'ed out.


Correct on all three.

Thx for the confirmation.

I see that differential as apposed to absolute sensors are much cheaper. Might consider that.

Sorry, wrong term. I meant guage. not differential. Digi-key has em for about $15. 0-50 PSIG

Thanks Fingers, you have to get a life.

speaking of digi-key, they have controller circuitry (WI application), is it worth pursuing? I looked at them, but that is all latin to me.

Referring to the edge attitude boost reading, is this where the signal originates? Is the edge signal a mathematical combination of the boost and baro sensors?

Referring to the edge attitude boost reading, is this where the signal originates? Is the edge signal a mathematical combination of the boost and baro sensors?


No, Attitude engine data appears to come from tapping the CAN buss.

And the CAN bus get's it's boost data from....?

The CAN bus is the inter-controller bus used by all of the different CPU's on the truck. Similar to OBD2, but much faster/better. The Attitude is getting the data from the PCM data stream.

You are smarter than anyone has a right to be:D . But the question!):h

Where does the edge boost signal, have it's origin? Must be the map sensor or something else.