LM7 4 Lower-Block Sensor Identification

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05-14-2013, 05:01 PM

digitalfiend

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LM7 4 Lower-Block Sensor Identification

Howdy Ya'll!
I've got a flex-fuel LM7 that came out of a 2009 Tahoe Police cruiser. I'm trying to identify four sensors on the block. There are two on each side underneath the heads. Does anyone know what these things do???

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05-14-2013, 08:31 PM

S10xGN

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The two that are "bolted on" are knock sensors, the one behind the starter motor is the crank position sensor. The other... It looks to be in the oil galley so it may be a pressure sensor, but I've never seen one there.

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05-14-2013, 09:20 PM

digitalfiend

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Quote:

Originally Posted by S10xGN

Crank position sensor? That does make sense.

I'm a little confused about the knock sensors...I thought those were underneath the intake between cylinder heads. Are the ones on the side of the block *additional* knock sensors?

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05-15-2013, 10:54 AM

Remnant-of-VII

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Nope. Those are it. They moved them to the sides of the block to make room for the D.O.D. (Displacement on Demand.) that GM put in the valley around '07.