[V8] Knock sensor#1

[urq]

... good point ... it may be an issue with bad gas causing an intermittent
code.  I checked SJMautotechnik and saw:

2142 Knock sensor #1
  Open or short circuit, Defective sensor
  Check sensor and wiring
  Symptom: Timing retarded, High fuel consumption, power loss

Which does look like a hardware problem ... after doing the resistance
checks you may want to clear the code and see if it returns.  If you find
the reading to be OK at the sensor and the codes return you might want to
check the resistance at the ECU.  

Steve B
San José, CA (USA)

-----Original Message-----
Subject: Re: [V8] Knock sensor#1

I bet the KS itself is not the problem. 
I seem to get that code with every fart the car makes, new KS on both or
not. 





----- Original Message -----
From: v8-bounces at audifans.com <v8-bounces at audifans.com>
To: cobram at juno.com <cobram at juno.com>
Cc: v8 at audifans.com <v8 at audifans.com>
Sent: Wed Jan 09 22:15:36 2008
Subject: Re: [V8] Knock sensor#1

I think the manual diagnostic procedure will allow you to check ohms on 
the sensor AND check continuity on the ECU wiring.  Page 28-110 says 
that there should be OPEN circuit between all three terminals (infinite 
ohms) and then some ways to check between ECU and wiring.

 From what I can recall, a knock sensor is normally open and when it is 
subject to the specific high frequency vibration that spark-knock 
produces, a piece of metal on the inside makes contact and completes the 
circuit.  The computer detects this as knocking and retards the timing 
until such signals cease.

~Scott S.

cobram at juno.com wrote:

>Last time I got a bad knock sensor code (Left bad), I swapped the
>connectors (L to R and R to L), still got the same code (Left bad.) 
>Ended up being a bad ECU, swapped it out with ECU from V8Q #2 and no more
>codes, put #1's ECU into #2 and got the bad knock sensor code.  It was
>definitely very detrimental to performance and fuel economy, car felt
>like it had a new engine, I think the rest of the ECU was defaulting to
>pre programmed timing etc. because of the reported bad knock sensor. 
>
>BCNU,
>http://www.geocities.com/cobramsri/
>Democracy: 3 wolves and a sheep voting on what's for lunch.
>
> Scott Simmons <indischrot at gmail.com> writes:
>  
>
>>I'd check the sensor before removal.  The manual has resistance 
>>checks 
>>you can do, and since the connector is RIGHT THERE on top of the 
>>motor... I'd do that first.
>>