Knock Sensor Error Code - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

*HaLo* · 07-31-2002, 08:49 PM

Hi there,

I've checked my ECU error codes today and I got a code 34: knock sensor.  

A little later, I reset the ECU and did a little 2 minute drive and the code 34 didn't come on?

What should I do next?  Should I assume everything is fine (code 55) or that I have some sort of problem around my knock sensor?

If I do have a problem, should I change the whole part? Is it hard to change? How much is the part?  

I'd like your input.  Thanks a lot!

SSJ2Gohan · 07-31-2002, 09:32 PM

I think you may be alright.  From what I understand the code will come back if there is a problem.

Everytime I clean my engine it puts the light on.  Says my O2 sensor went out.  So I replaced it.  Next time same thing.  Replaced again.  next time I finally caught on.  Reset my ecu and never saw it again.  Just cleaned my engine about a month ago and guess what?  It went back on!  This time I just ignored it and it turned off by itself (I think it goes away after 50 starts if the problem doesnt exist.

bbp · 08-01-2002, 07:32 AM

The knock sensor is bolted to the engine and reads ultra high frequency vibration from the motor.  It senses the vibrations when the engine is experienceing pre-detonation and adjust the engine mangement to compensate.  The car will run without the sensor, it will trip a trouble code though.  The sensor is very expensive and does not like to be dropped, tapped on or anything like that.

It is insurance that a bad mixture doesn't tank the motor.

*HaLo* · 08-01-2002, 10:59 AM

Ok... I checked again today and it gave me the code again.  

Does this mean it has to be replaced?

bbp · 08-01-2002, 02:58 PM

it doesn't "have" to be replaced.  I think Ipriced them at over 150 bucks.  ask you dealer's tech.  see what they say.  i took mine out odf the race car, but we check the plugs quite often and run race fuel to prevent pinging.

*HaLo* · 08-01-2002, 04:40 PM

Well... I asked the dealer.  They quoted me 172 C$ for the sensor.  He also said that it could be the circuit (wires) itself.  Does someone know where to start to check that circuit?

Also, would a faulty knock sensor reduce overall performance of the car?

Mtt22 · 08-01-2002, 04:53 PM

can someone how to check yoru error codes, or point me at a faq, 240sx.org is down so i couldnt check there.  Do you need a code reader?

*HaLo* · 08-02-2002, 04:27 PM

Anyone?!

07-31-2002, 08:49 PM	#1
HaLo from Canada, eh! Join Date: Sep 2001 Location: Montreal, Quebec Age: 46 Posts: 5,201 Trader Rating: (0) Rides Gallery: HaLo Feedback Score: 0 reviews	Hi there, I've checked my ECU error codes today and I got a code 34: knock sensor.   A little later, I reset the ECU and did a little 2 minute drive and the code 34 didn't come on? What should I do next?  Should I assume everything is fine (code 55) or that I have some sort of problem around my knock sensor? If I do have a problem, should I change the whole part? Is it hard to change? How much is the part?   I'd like your input.  Thanks a lot! __________________ -> HaLo Race Car: '98 E36 BMW M3 Daily Drivers: '23 Audi Q4 e-tron & '13 VW Touareg SOLD: 01 GPW Honda S2000 PARTED: 93 Pearl White 240SX LE Fastback w/SR20DET SOLD: 93 Super White 240SX SE Convertible w/Silvia Front

07-31-2002, 09:32 PM	#2
SSJ2Gohan Leaky Injector Join Date: Feb 2002 Posts: 149 Trader Rating: (0) Feedback Score: 0 reviews	I think you may be alright.  From what I understand the code will come back if there is a problem. Everytime I clean my engine it puts the light on.  Says my O2 sensor went out.  So I replaced it.  Next time same thing.  Replaced again.  next time I finally caught on.  Reset my ecu and never saw it again.  Just cleaned my engine about a month ago and guess what?  It went back on!  This time I just ignored it and it turned off by itself (I think it goes away after 50 starts if the problem doesnt exist. __________________ Kamehameha!

08-01-2002, 07:32 AM	#3
bbp Zilvia Junkie Join Date: Apr 2002 Location: oHIo Age: 53 Posts: 477 Trader Rating: (0) Feedback Score: 0 reviews	The knock sensor is bolted to the engine and reads ultra high frequency vibration from the motor.  It senses the vibrations when the engine is experienceing pre-detonation and adjust the engine mangement to compensate.  The car will run without the sensor, it will trip a trouble code though.  The sensor is very expensive and does not like to be dropped, tapped on or anything like that. It is insurance that a bad mixture doesn't tank the motor. __________________

08-01-2002, 10:59 AM	#4
HaLo from Canada, eh! Join Date: Sep 2001 Location: Montreal, Quebec Age: 46 Posts: 5,201 Trader Rating: (0) Rides Gallery: HaLo Feedback Score: 0 reviews	Ok... I checked again today and it gave me the code again.   Does this mean it has to be replaced? __________________ -> HaLo Race Car: '98 E36 BMW M3 Daily Drivers: '23 Audi Q4 e-tron & '13 VW Touareg SOLD: 01 GPW Honda S2000 PARTED: 93 Pearl White 240SX LE Fastback w/SR20DET SOLD: 93 Super White 240SX SE Convertible w/Silvia Front

08-01-2002, 02:58 PM	#5
bbp Zilvia Junkie Join Date: Apr 2002 Location: oHIo Age: 53 Posts: 477 Trader Rating: (0) Feedback Score: 0 reviews	it doesn't "have" to be replaced.  I think Ipriced them at over 150 bucks.  ask you dealer's tech.  see what they say.  i took mine out odf the race car, but we check the plugs quite often and run race fuel to prevent pinging. __________________

08-01-2002, 04:40 PM	#6
HaLo from Canada, eh! Join Date: Sep 2001 Location: Montreal, Quebec Age: 46 Posts: 5,201 Trader Rating: (0) Rides Gallery: HaLo Feedback Score: 0 reviews	Well... I asked the dealer.  They quoted me 172 C$ for the sensor.  He also said that it could be the circuit (wires) itself.  Does someone know where to start to check that circuit? Also, would a faulty knock sensor reduce overall performance of the car? __________________ -> HaLo Race Car: '98 E36 BMW M3 Daily Drivers: '23 Audi Q4 e-tron & '13 VW Touareg SOLD: 01 GPW Honda S2000 PARTED: 93 Pearl White 240SX LE Fastback w/SR20DET SOLD: 93 Super White 240SX SE Convertible w/Silvia Front

08-01-2002, 04:53 PM	#7
Mtt22 Leaky Injector Join Date: Jun 2002 Posts: 79 Trader Rating: (0) Feedback Score: 0 reviews	can someone how to check yoru error codes, or point me at a faq, 240sx.org is down so i couldnt check there.  Do you need a code reader? __________________ Matt "andy offers kevin pudding at 9, if andy is 7 years older then pudding than how many liters of andy does it take to get to detroit?" "There are 3 types of people in this world. People who can count, and people who cant.." ""Save the Whales" (Trade them for valuable prizes)"

08-02-2002, 04:27 PM	#8
HaLo from Canada, eh! Join Date: Sep 2001 Location: Montreal, Quebec Age: 46 Posts: 5,201 Trader Rating: (0) Rides Gallery: HaLo Feedback Score: 0 reviews	Anyone?! __________________ -> HaLo Race Car: '98 E36 BMW M3 Daily Drivers: '23 Audi Q4 e-tron & '13 VW Touareg SOLD: 01 GPW Honda S2000 PARTED: 93 Pearl White 240SX LE Fastback w/SR20DET SOLD: 93 Super White 240SX SE Convertible w/Silvia Front