Constant knock sensor code - 850R

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1992 - 1997 850, 850 R, 850 T5-R, 850 T5, 850 GLT
1997 - 2000 S70, S70 AWD
1997 - 2000 V70, V70 AWD
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jnewt
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Year and Model: 1991 244
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Constant knock sensor code - 850R

Post by jnewt »

Knock sensor code tripped when I was going 30mph barely any throttle. When I clear the code it comes on immediately after restarting the car, within a second or two at most. Is it possible to reach the sensors without removing the manifold?

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erikv11
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Post by erikv11 »

It's really tough to reach them but you can.

This code is almost never an actual knock sensor problem - usually the wiring is damaged or connections are dirty.
'95 854 T5-R, Motronic 4.4, 185k
'96 855 NA, 145k
'98 S70 NA, 220k (living out west)
'98 V70, T5 tune-injectors-turbo, LPT engine, 293k
'06 S60 R, 167k
'07 XC70, 170k
'99 Camry V6 :shock: 130k
gone: '96 NA 850 210k, '98 NA V70 182k

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abscate
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Post by abscate »

What year is this? What code is being read? Many readers don’t map the p code to text correctly
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jnewt
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Post by jnewt »

abscate wrote: Sun Aug 23, 2020 4:07 am What year is this? What code is being read? Many readers don’t map the p code to text correctly
1996, code P0326 - Knock Sensor 1 Circuit Range/Performance (Bank 1) is the exact text

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Post by abscate »

You will find very few clear this code with replacing the knock sensors, it’s usually poor running, wiring, or corrosion

Don’t overtughten the sensor or you will break them. Look up the spec torque, it’s low. Can’t be too loose either
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850oldschool
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Post by 850oldschool »

It’s possible to wriggle your hand in there. and also to view with a mirror. My wire was severed, perhaps by a rodent.

jnewt
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Post by jnewt »

abscate wrote: Sun Aug 23, 2020 8:39 am You will find very few clear this code with replacing the knock sensors, it’s usually poor running, wiring, or corrosion

Don’t overtughten the sensor or you will break them. Look up the spec torque, it’s low. Can’t be too loose either
I reached my hand behind the intake manifold and wiggled the connector a bit and now no more code, I’m almost certain it’s the wiring and I’ll have to get in there to fix it. Thanks

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