Connector Wiring Pin Numbers. This is the one that caused the most heartburn. As several previous commenters have noted, and as I found myself, the pin numbers cited in the video did not correctly correspond with the numbers on the large wiring harness connector (the C149 connector, or Super Multiple Junction in Nissan lingo). I couldn’t find where anyone had adequately responded to this issue and I can’t totally clear things up, but here is what I was able to find before finally having the courage to cut the wire. A 1999 Nissan Quest Repair Manual shows the connector pins to be exactly as stated in this video. Looking from the front of the vehicle towards the passenger compartment, the pin locations are stated to be as follows: top right is pin 1, bottom right is pin 9, and top left is pin 34, and bottom left is pin 42. The KS signal wire is stated as being a white wire in pin 37, 4 pins below the top left pin (the KS ground is stated to be running through pin 29, but I did not confirm this). That’s all great, but when I looked at my connector, it is laid out as follows: top right is labeled pin 42, bottom right is pin 34, and top left is pin 9, and bottom left is pin 1. The white wire is in pin 6. So is the KS signal wire the white wire in pin 6, or whatever color wire is in pin 37? I resolved this by comparing the wire colors as stated in the repair manual for pins 34 through 42 and pins 1 through 9 to the physically corresponding pins on my connector (i.e., pins 9 through 1 and pins 42 through 34 respectively). The wire colors matched perfectly, so it appears as though the wire locations are as stated, but the pin numbers are not. I have no idea how this came about. The only thing I can imagine is that either the pin numbers are different for Ford versus Nissan or the part was manufactured differently than designed. Neither seems likely, but it is clear that the KS signal wire is in the fourth pin down from the top left pin of the connector (looking from the front of the vehicle toward the passenger compartment). In my case, this was pin 6 (white wire). Sorry to be so verbose, but I want to be as clear as possible since cutting the wrong wire was a big worry for me.
KS Wiring Connector Mods. This is just personal preference, but I attached the KS to the 28423 connector by (carefully) sawing off about a half inch (just at the point where the plastic “fins” stick up from the sheath) of the sheath that surrounds the KS pins. This removes the “fins” from the sheath (while still retaining adequate sheathing to cover the pins) and allows the KS and the connector to fit together snugly without mods to the connector (also allowing the connector “locking” mechanism to be used as designed).
Clarification in case the author does not see the comments. What he is saying is the knock sensor wire--when the video shows the back IS THE THIRD WIRE DOWN--he mentions "one is blank"--ITS THE THIRD WIRE. Its 4 spots down but one is just a blank spot of plastic. Also--the ground wire is the clip ON THE RIGHT--if you are holding and looking at the sensor. That ground wire is optional--its actually not necessary since the PCM is grounded to the engine. BETTER TO JUST ADD IT ANYWAY just in case.
Thanks again--you blazed the trail plus gave the various part numbers and the wire to cut--I simply improved on it and took close up pictures. If not for your video I had zero idea where to start. also alot of times people go to the trouble to help others and upload a video like you did--then people often nitpic it. but that one bolt is metric 8mm X 1.25 X 30mm the 30mm is the length of the threads for a good half inch engagment. You can swap yours over in seconds. also that same plug in IS IDENTICAL FOR THE CRANKSHAFT POSITION SENSOR--its a common plug in. the contact pins are the same--its a universal plug in.
Tony gave me the guts to try it so I uploaded a video with some improvments expanding on his video in case you stumble upon this. For the plug in part--it is far easier to simply clip away the plastic collar with wirecutters and file a bit on the remaining collar remnants. That way you have the perfect plug freed up from the huge plastic molding that hides the plug pins. Also its a much better install to simply ground under the distributor bolt--do not be nervous about the distributor its just a ground onto the block and affects the distributor not in the slightest. Also the ground wire IS NOT REALLY NEEDED--once the wire from the knock sensor is connected to the cut wire behind the harness THE SENSOR IS GROUNDED THROUGH THE COMPUTER. But your better off attaching the ground wire FOR PEACE OF MIND. Also when you plug in to the sensor--USE SILICONE TO HERMETICALLY SEAL IT--THEN WRAP IT WITH ELECTRICAL TAPE FOR PROFESSIONAL LOOK The plug in--and the knock sensor should then be a sealed permanent unit. There is zero reason to be unplugging it anyway for the life of the vehicle.
of you get this within the next few minutes. ... the wires on the harness are both white. does it matter witch one hooks to the big harness? need to know ASAP
nice video Tony, this really helped saved $450! I did place KS below the connector. just connected the white wire only behind C149. Used Metric screw. The case of KS is ground so if you screw to chassis continuity is OK
UPDATE ON THIS-- the thickness of the sensor is more than 3/4 about .780. The THREADS of the bolt need to be well over 1 inch or it will barely engage one or 2 threads. Also its NOT 5/16--18. Its metric its M8--1.25---x 30mm. that exact SOCKET HEAD CAP SCREW is at home depot. That gives good thread engagement of about a half inch. 5/16-18 if the bolt is short--WILL start to grab--because the lead and pitch is CLOSE to the metric.
The KS Bolt. The pre-drilled hole is indeed metric M8x1.25, but I used 40 mm rather than 30 mm to ensure full seating of the knock sensor (KS). The KS is about 20 mm thick, so a 30 mm bolt provides a seat of about 10 mm (about 4 tenths of an inch). A 40 mm bolt doubles that and the pre-drilled hole easily accommodates the 40 mm bolt. The maximum depth of the hole is about 25 mm (measured imprecisely), so a 45 mm bolt might seat, but nothing longer.
Hi this video really helped us on are po325 knock sensor code for the Nissan Quest Van. Nobody else new anything how to fix . will be sharing this video on facebook
Splice into the Front of Connector. I spliced into the original KS white circuit wire in front, rather than in back, of the large wiring harness connector (the C149 connector, or Super Multiple Junction in Nissan lingo). There is a lot more room to work in front and the connector is simply a pass through. If you do this, splice into the cut portion of the white wire that is not going to the connector (it is going to the engine computer) and leave the remnant coming from the connector orphaned.
First, kudos to Tony and Jeff C. as I would not have attempted this without either of these guys’ videos and suggestions. In undertaking the repair, I did run into a few issues and develop a few clarifications that I thought I would post here in case they help anyone. There are five items and I’ll post them individually to avoid a ridiculously long post.
It might be better to use BWD Ignition Knock (Detonation) Sensor Advance Auto P/N S8759. This KS comes with wires attached to it. You will eliminate the pigtail and problems with having to cut slots on the pigtail or shave the KS to make it fit. Just cut off the connector from the KS and splice the 18 gauge wire to the KS wire
Advance Auto has another pigtail which appears to be a better fit without having to cut slots in it or shaving the knock sensor. CARQUEST by BWD pigtail P/N 28419A.
the new sensor hole on my car is not 5/16" - 18. It is a metric thread M8 1.25. You can force a 5/16" - 18 into the hole but if your hole thread is the same as mine (which I suspect is true) I recommend using the proper bolt size. Otherwise, if it is removed and reinstalled in the future it may not hold very well.
Tony2005 contour thanks for the video. I successfully relocated the KS. However my break lights are continuously on now and cruise control doesn’t work. Both worked before I did this relocation. Do you know what would be the cause of this?
Grounding the KS. The original KS is, indeed, grounded through the engine computer. However, the ground for the original KS is not relevant to the relocated KS, unless the relocated KS is spliced into the original KS ground. One way or the other, the relocated KS does need to be grounded. Because it was easier than splicing into the original KS ground, I grounded the relocated KS to an existing sidewall ground screw behind the cruise control servo (the 4.5 inch or so disc shaped housing with a cable running from its center that sits above the passenger side front wheel well). I’m not an electrician so I could have this all wrong, but that’s my thinking on this.
My 2000 Nissan Quest felt like it lost a lot of hp. Eventually, the ECM coded and indicated a defective knock sensor. Using the relocation idea, I replaced the existing knock sensor. One wire to the lead and the other to ground. I found the M8 bolt at Home Depot. My guess is the old knock sensor was bad for a long time because when I replaced it the truck had more power. The old sensor must have been retarding the timing because the engine has more power since the change.
I know this is an old post, but why not get the specific replacement KS & wire harness for the vehicle , cut the end of the wire harness and wire that in front of the C149? Same concept but way easier or am I wrong for some reason?
Hello. After cutting wire 37, did you connect the new K/S to the wire going into the back of C149(the approximately 2" piece) or the wire leading down into the wire conduit? Thank you very much for this helpful video. You have saved many people a tremendous amount of money with this tutorial. Again, thank you and have a great day.
+John Grubbs Hello: Did you ever figure out your wire question? I am facing the same issue currently. Do I connect the new k/s wire to the wire going back into the back of c149, or into the wire leading down into the wire conduit? I have the same fork in the road to figure out. Any suggestions. DC
+Olivia Cole Hello. I connected my new K/S wire to the approximately 2" wire going into the back of C149(the little black square connector). This relocation has worked perfectly for me ever since. A huge thank you to Tony2005 contour for posting this tutorial. May you have a great day.
Hey I had a question my dad replaced all sensors on 2000 mercury villager went to get inspection said he hasn’t drove around enough but o2 light came on after he left
I'm getting ready to relocate the knock sensor on my in-laws 1996 mercury villager and was wondering where I could relocate the k/s since there is no spot below the distributor to mount the sensor. any help would be appreciated. thanks.
I also have a 1996 quest which happens to need a new knock sensor. Did you ever find a spot to install your KS? Please share any suggestions. Thank you.
yes there is on nissan forums but warning--the directions are complex and mixed up. such as part number for electrical tape. The other directions on nissan do mention ground wire is optional not really needed. I will upload a video when I finish mine im waiting on the sensor.
+tim assaf The knock sensor had malfunctioned resulting in a P0325 code. While this did not turn on the CEL/SES light, during emissions testing, it will show up when the inspector checks for codes (emissions testing required once very two years). Hence, the vehicle will fail the test. In addition, while the drivability does not appear to be impaired, it will result in "knocking" when the engine does not fire properly or when the octane level is too low. A working knock sensor senses the engine at the point of just "knocking" and it retards the engine timing to reduce/eliminate the "knocking".
+Tony2005 contour If I did not relocate the knock sensor, I would have to remove the upper and lower intake manifold, and the coolant crossover pipes to get to the knock sensor.
hello +Tony2005 contour, first a lot of thanks for the video, help me so much, i have a question, the left terminal is the K/S wire and the right terminal is the ground wire?? cause in the vid does not shows that well, thank you!!
Mike Westfall if it is the knock sensor, then yes, it will fix it. chances are it is a pinhole leak in a hose next to fuel injector 3. that is very prevalent in 99 villagers. you live with it or have them take out the upper intake manifold to remove and replace it. and the hose might not be available anymore.
Connector Wiring Pin Numbers. This is the one that caused the most heartburn. As several previous commenters have noted, and as I found myself, the pin numbers cited in the video did not correctly correspond with the numbers on the large wiring harness connector (the C149 connector, or Super Multiple Junction in Nissan lingo). I couldn’t find where anyone had adequately responded to this issue and I can’t totally clear things up, but here is what I was able to find before finally having the courage to cut the wire. A 1999 Nissan Quest Repair Manual shows the connector pins to be exactly as stated in this video. Looking from the front of the vehicle towards the passenger compartment, the pin locations are stated to be as follows: top right is pin 1, bottom right is pin 9, and top left is pin 34, and bottom left is pin 42. The KS signal wire is stated as being a white wire in pin 37, 4 pins below the top left pin (the KS ground is stated to be running through pin 29, but I did not confirm this). That’s all great, but when I looked at my connector, it is laid out as follows: top right is labeled pin 42, bottom right is pin 34, and top left is pin 9, and bottom left is pin 1. The white wire is in pin 6. So is the KS signal wire the white wire in pin 6, or whatever color wire is in pin 37? I resolved this by comparing the wire colors as stated in the repair manual for pins 34 through 42 and pins 1 through 9 to the physically corresponding pins on my connector (i.e., pins 9 through 1 and pins 42 through 34 respectively). The wire colors matched perfectly, so it appears as though the wire locations are as stated, but the pin numbers are not. I have no idea how this came about. The only thing I can imagine is that either the pin numbers are different for Ford versus Nissan or the part was manufactured differently than designed. Neither seems likely, but it is clear that the KS signal wire is in the fourth pin down from the top left pin of the connector (looking from the front of the vehicle toward the passenger compartment). In my case, this was pin 6 (white wire). Sorry to be so verbose, but I want to be as clear as possible since cutting the wrong wire was a big worry for me.
If was little bit smarter JUST TO ROTATE a connector at 180 degr, you will be surprised how all pins and numbers appear at their places as manual says
KS Wiring Connector Mods. This is just personal preference, but I attached the KS to the 28423 connector by (carefully) sawing off about a half inch (just at the point where the plastic “fins” stick up from the sheath) of the sheath that surrounds the KS pins. This removes the “fins” from the sheath (while still retaining adequate sheathing to cover the pins) and allows the KS and the connector to fit together snugly without mods to the connector (also allowing the connector “locking” mechanism to be used as designed).
Clarification in case the author does not see the comments. What he is saying is the knock sensor wire--when the video shows the back IS THE THIRD WIRE DOWN--he mentions "one is blank"--ITS THE THIRD WIRE. Its 4 spots down but one is just a blank spot of plastic. Also--the ground wire is the clip ON THE RIGHT--if you are holding and looking at the sensor. That ground wire is optional--its actually not necessary since the PCM is grounded to the engine. BETTER TO JUST ADD IT ANYWAY just in case.
Jeff C thanks. I seldom come on this site.
Thanks again--you blazed the trail plus gave the various part numbers and the wire to cut--I simply improved on it and took close up pictures. If not for your video I had zero idea where to start. also alot of times people go to the trouble to help others and upload a video like you did--then people often nitpic it. but that one bolt is metric 8mm X 1.25 X 30mm the 30mm is the length of the threads for a good half inch engagment. You can swap yours over in seconds. also that same plug in IS IDENTICAL FOR THE CRANKSHAFT POSITION SENSOR--its a common plug in. the contact pins are the same--its a universal plug in.
Tony gave me the guts to try it so I uploaded a video with some improvments expanding on his video in case you stumble upon this. For the plug in part--it is far easier to simply clip away the plastic collar with wirecutters and file a bit on the remaining collar remnants. That way you have the perfect plug freed up from the huge plastic molding that hides the plug pins. Also its a much better install to simply ground under the distributor bolt--do not be nervous about the distributor its just a ground onto the block and affects the distributor not in the slightest. Also the ground wire IS NOT REALLY NEEDED--once the wire from the knock sensor is connected to the cut wire behind the harness THE SENSOR IS GROUNDED THROUGH THE COMPUTER. But your better off attaching the ground wire FOR PEACE OF MIND. Also when you plug in to the sensor--USE SILICONE TO HERMETICALLY SEAL IT--THEN WRAP IT WITH ELECTRICAL TAPE FOR PROFESSIONAL LOOK The plug in--and the knock sensor should then be a sealed permanent unit. There is zero reason to be unplugging it anyway for the life of the vehicle.
Jeff C thanks for posting
of you get this within the next few minutes. ... the wires on the harness are both white. does it matter witch one hooks to the big harness? need to know ASAP
and why cant you cut into the front instead of the back
nice video Tony, this really helped saved $450! I did place KS below the connector. just connected the white wire only behind C149. Used Metric screw. The case of KS is ground so if you screw to chassis continuity is OK
UPDATE ON THIS-- the thickness of the sensor is more than 3/4 about .780. The THREADS of the bolt need to be well over 1 inch or it will barely engage one or 2 threads. Also its NOT 5/16--18. Its metric its M8--1.25---x 30mm. that exact SOCKET HEAD CAP SCREW is at home depot. That gives good thread engagement of about a half inch. 5/16-18 if the bolt is short--WILL start to grab--because the lead and pitch is CLOSE to the metric.
The KS Bolt. The pre-drilled hole is indeed metric M8x1.25, but I used 40 mm rather than 30 mm to ensure full seating of the knock sensor (KS). The KS is about 20 mm thick, so a 30 mm bolt provides a seat of about 10 mm (about 4 tenths of an inch). A 40 mm bolt doubles that and the pre-drilled hole easily accommodates the 40 mm bolt. The maximum depth of the hole is about 25 mm (measured imprecisely), so a 45 mm bolt might seat, but nothing longer.
Your tips are great. Thanks
Hi this video really helped us on are po325 knock sensor code for the Nissan Quest Van. Nobody else new anything how to fix . will be sharing this video on facebook
Splice into the Front of Connector. I spliced into the original KS white circuit wire in front, rather than in back, of the large wiring harness connector (the C149 connector, or Super Multiple Junction in Nissan lingo). There is a lot more room to work in front and the connector is simply a pass through. If you do this, splice into the cut portion of the white wire that is not going to the connector (it is going to the engine computer) and leave the remnant coming from the connector orphaned.
All of your tips were great. It made installation a breeze. The hardest part was shaving down the harness. Thanks!
Thank you so much for this Video. Bless you Tony2005 You helped me save up to 300 dollars and lots of headaches
First, kudos to Tony and Jeff C. as I would not have attempted this without either of these guys’ videos and suggestions. In undertaking the repair, I did run into a few issues and develop a few clarifications that I thought I would post here in case they help anyone. There are five items and I’ll post them individually to avoid a ridiculously long post.
Is there a specific ground wire coming from the Knock Sensor? Or can you use either wire for the ground?
Thank great video I will used for connect my knot sensor God Bless you
It might be better to use BWD Ignition Knock (Detonation) Sensor Advance Auto P/N S8759. This KS comes with wires attached to it. You will eliminate the pigtail and problems with having to cut slots on the pigtail or shave the KS to make it fit. Just cut off the connector from the KS and splice the 18 gauge wire to the KS wire
Advance Auto has another pigtail which appears to be a better fit without having to cut slots in it or shaving the knock sensor. CARQUEST by BWD pigtail P/N 28419A.
the new sensor hole on my car is not 5/16" - 18. It is a metric thread M8 1.25. You can force a 5/16" - 18 into the hole but if your hole thread is the same as mine (which I suspect is true) I recommend using the proper bolt size. Otherwise, if it is removed and reinstalled in the future it may not hold very well.
You should use the correct bolt size if the engine had a different bolt size. Thanks for posting.
Tony2005 contour thanks for the video. I successfully relocated the KS. However my break lights are continuously on now and cruise control doesn’t work. Both worked before I did this relocation. Do you know what would be the cause of this?
Grounding the KS. The original KS is, indeed, grounded through the engine computer. However, the ground for the original KS is not relevant to the relocated KS, unless the relocated KS is spliced into the original KS ground. One way or the other, the relocated KS does need to be grounded. Because it was easier than splicing into the original KS ground, I grounded the relocated KS to an existing sidewall ground screw behind the cruise control servo (the 4.5 inch or so disc shaped housing with a cable running from its center that sits above the passenger side front wheel well). I’m not an electrician so I could have this all wrong, but that’s my thinking on this.
awesome job thank you for the video
My 2000 Nissan Quest felt like it lost a lot of hp. Eventually, the ECM coded and indicated a defective knock sensor. Using the relocation idea, I replaced the existing knock sensor. One wire to the lead and the other to ground. I found the M8 bolt at Home Depot. My guess is the old knock sensor was bad for a long time because when I replaced it the truck had more power. The old sensor must have been retarding the timing because the engine has more power since the change.
Connect the new wire to the back of C149. C149 leads to the PCM. You want the signal to go to the PCM
+Tony2005 contour ----Ok. Got it. Thanks for such a quick response. Your help is kindly received.
I know this is an old post, but why not get the specific replacement KS & wire harness for the vehicle , cut the end of the wire harness and wire that in front of the C149? Same concept but way easier or am I wrong for some reason?
Is there a specific ground wire coming from the Knock Sensor? Or can you use either wire for the ground?
Hello. After cutting wire 37, did you connect the new K/S to the wire going into the back of C149(the approximately 2" piece) or the wire leading down into the wire conduit? Thank you very much for this helpful video. You have saved many people a tremendous amount of money with this tutorial. Again, thank you and have a great day.
+John Grubbs Hello: Did you ever figure out your wire question? I am facing the same issue currently. Do I connect the new k/s wire to the wire going back into the back of c149, or into the wire leading down into the wire conduit? I have the same fork in the road to figure out. Any suggestions.
DC
+Olivia Cole Connect the new wire to the back of C149. C149 leads to the PCM. You want the signal to go to the PCM
+Olivia Cole Hello. I connected my new K/S wire to the approximately 2" wire going into the back of C149(the little black square connector). This relocation has worked perfectly for me ever since. A huge thank you to Tony2005 contour for posting this tutorial. May you have a great day.
Hey I had a question my dad replaced all sensors on 2000 mercury villager went to get inspection said he hasn’t drove around enough but o2 light came on after he left
by any chance i have is my scenor located infront of the motor i have a 2001 Nissan quest is that the scenor
Is this the same as putting it on the engine block? Because that is putting it on the head and not the block at all.
cool video just by looking piece of cake
Ring Master yes, it is
I've also been haveing a hard time finding KS s8759
I'm getting ready to relocate the knock sensor on my in-laws 1996 mercury villager and was wondering where I could relocate the k/s since there is no spot below the distributor to mount the sensor. any help would be appreciated. thanks.
I also have a 1996 quest which happens to need a new knock sensor. Did you ever find a spot to install your KS? Please share any suggestions. Thank you.
What is the top of the pigtail is it the part that is kinda cut in a C or is it the flat side
What your saying to connect ks wire mine is pin 4 or if I go with pin 37 it's on opposite side with orange wire HELP!!
+Tony2005 contour, is there a link where I can download these instructions to relocate the knock sensor on a 1997 mercury villager?
did you ever get a response for this question?
+Sean Hart no my knock sensor eventually fixed itself...
is there a place for this to be found? and printed
yes there is on nissan forums but warning--the directions are complex and mixed up. such as part number for electrical tape. The other directions on nissan do mention ground wire is optional not really needed. I will upload a video when I finish mine im waiting on the sensor.
Jeff,
I know this was 5 years ago. Did you upload a video. I’m doing it on a 96 quest.
does this works for 2000 nissan quest or is just for 99?
what was the issue that you decided to replace and relocate the knock sensor.
was there a driveability issue?
or just a code. thanks.
+tim assaf The knock sensor had malfunctioned resulting in a P0325 code. While this did not turn on the CEL/SES light, during emissions testing, it will show up when the inspector checks for codes (emissions testing required once very two years). Hence, the vehicle will fail the test. In addition, while the drivability does not appear to be impaired, it will result in "knocking" when the engine does not fire properly or when the octane level is too low. A working knock sensor senses the engine at the point of just "knocking" and it retards the engine timing to reduce/eliminate the "knocking".
+Tony2005 contour If I did not relocate the knock sensor, I would have to remove the upper and lower intake manifold, and the coolant crossover pipes to get to the knock sensor.
Has anyone tried KS s8741? It has the wires build into it and also has a stud built in, I'd guess the stud is 8mmx1.25 size?
hello +Tony2005 contour, first a lot of thanks for the video, help me so much, i have a question, the left terminal is the K/S wire and the right terminal is the ground wire?? cause in the vid does not shows that well, thank you!!
Yes, looking into the Knock Sensor socket, the left side should be the KS White wire and the right side should be the ground black wire.
thank u so much
I have a low idle miss in my 99 villager Meinike said it was due to a knock sensor short in the harness ,Will this fix it?
Mike Westfall if it is the knock sensor, then yes, it will fix it. chances are it is a pinhole leak in a hose next to fuel injector 3. that is very prevalent in 99 villagers. you live with it or have them take out the upper intake manifold to remove and replace it. and the hose might not be available anymore.
Mike Westfall r& r uim = $1000
So, all you did was rewire everything?
Good video great accent can we see a couple cute little Asian girls
.
Slow down on the fuckin camera