1990 Lexus ES 1990 Lexus ES250 knock sensor replacement

1990 LEXUS ES
18,400 MILES • 6 CYL • FWD • AUTOMATIC
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DWHEELER7676
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The Check Engine Light is on, code indicates a knock sensor failure of some sort. Engine currently fails [MD] state emissions tests for high NO2 (needs EGR valve?), but otherwise runs fine. The knock sensor lists for around $200 (I may need two?).

Does anyone know where are the darn things are physically located? (My crappy repair manual just says atop the engine block.) What does it take to change them? Is it worth it?

I'd especially be interested in feedback from someone who has actually done this themselves, or knows what's really involved, results, (cost?), etc.

Thanks in advance.
Jun 2, 2008 at 1:15 PM
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CARLIFE65
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under hood center, rear engina ara, below, intake manifold, mounted in engina block. disconnect the knock sensor wiring connector, then unscrew the sensor and remove it


https://www.2carpros.com/forum/automotive_pictures/420105_00126_knock_sensor_4.jpg

Oct 26, 2009 at 12:26 AM
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PROTECH1
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Located below the lower intake manifold, in the "v" section of the engine. This is a fairly labor intensive job, requiring intake gaskets, coolant, etc. Also be sure to inspect the wiring harness while in there. Ive seen the wires/connectors deteriorate due to heat.
I have performed this job quite a few times myself, being a Lexus technician.
Dec 7, 2009 at 1:02 PM
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PROTECH1
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Yes, there are 2 sensors in there.
Dec 7, 2009 at 1:03 PM