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Knock sensor bypass - Methods & Part Numbers
#26
Thread Starter
Re: (fallenasleepek)
The more noise and vibration the better.
Technically, the ideal location for the transducer would be on the block. It has to be on the intake side to avoid exhaust heat. But it's hard to find a place to attach it to the block. That's why I put it on the fuel rail and with good results.
And when I taped the tranducer on, I left some slack in the tape so that the sensor itself bounces around on the rail to create even more vibration.
Technically, the ideal location for the transducer would be on the block. It has to be on the intake side to avoid exhaust heat. But it's hard to find a place to attach it to the block. That's why I put it on the fuel rail and with good results.
And when I taped the tranducer on, I left some slack in the tape so that the sensor itself bounces around on the rail to create even more vibration.
#28
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Re: (pelon 1990 civic si)
i had to use two also on the i/m but def works now the first time i got discouraged cuz the light kept coming on but i just threw on the second sensor and whaalaaa ****** VTEC... lol mini-me now completed >>> THANKS man
#31
Thread Starter
Re: (fallenasleepek)
**UPDATE**
Well I finally got around to passing smog. As you know, you must log mileage into your ECU after it is reset otherwise you can't pas smog. After first installing the transducer, I drove around for a few days and my CEL came on at 50 miles. I reset the ECU and drove around for a few more days and the CEL came on again at 70 miles. I figured out that it was coming back on because my transducer was not making enough voltage and the ECU was realizing my hack.
So what I finally had to do was drive more agressively. Shift at higher RPMs and stay in fourth gear more often (not fifth). This increased the engine vibration which kept the transducer working. I drove around like this for about a week and no CEL. I was able to log 100 miles with no CEL and could finally smog it.
Well I finally got around to passing smog. As you know, you must log mileage into your ECU after it is reset otherwise you can't pas smog. After first installing the transducer, I drove around for a few days and my CEL came on at 50 miles. I reset the ECU and drove around for a few more days and the CEL came on again at 70 miles. I figured out that it was coming back on because my transducer was not making enough voltage and the ECU was realizing my hack.
So what I finally had to do was drive more agressively. Shift at higher RPMs and stay in fourth gear more often (not fifth). This increased the engine vibration which kept the transducer working. I drove around like this for about a week and no CEL. I was able to log 100 miles with no CEL and could finally smog it.
#33
Re: (SiViKbOi)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SiViKbOi »</TD></TR><TR><TD CLASS="quote">Has the CEL still come back after the 100 miles?</TD></TR></TABLE>
Well it probably would have, sooner or later, but after 100 miles I passed smog and pulled the thing off. It's not for long-term use, just to get you through smog.
Well it probably would have, sooner or later, but after 100 miles I passed smog and pulled the thing off. It's not for long-term use, just to get you through smog.
#34
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Re: I finally did it!!! Knock sensor bypass!! Woot! Woot! (JRciv)
This has to be the best 1.99 I have spent yet? You are the MAN!!! Have to 2nd appt. with BAR ref. and this was my last CEL problem.
One thing to add: In my case, the ref. last time went over my engine bay in detail. Not wanting to deal with why I had the transducer taped to the fuel rail. What I did was removed my shift boot, then the rubber dust seal, and mounted it in there. Nice and tucked away, with plenty of vibration. I haven't thrown a CEL since then. Works like a charm for me.
Thanks again for the awsome info.
One thing to add: In my case, the ref. last time went over my engine bay in detail. Not wanting to deal with why I had the transducer taped to the fuel rail. What I did was removed my shift boot, then the rubber dust seal, and mounted it in there. Nice and tucked away, with plenty of vibration. I haven't thrown a CEL since then. Works like a charm for me.
Thanks again for the awsome info.
#35
Re: I finally did it!!! Knock sensor bypass!! Woot! Woot! (DX_JDM_HATCH)
Glad I could help someone
I guess I had an easier time passing visual. The guy popped my hood and came face to face with $6k of aftermarket parts. He kind of looked confused then said "I don't even want to mess with this stuff." Lol. Then he shut the hood and that was it.
He was so dumb he didn't even notice the supercharger because when I was leaving he's like "you need more than just bolt-ons, you should get a turbo." I just played along and was like "yeah, I'll put a turbo on soon." It actually kind of sucked because I spent $30 buying the CARB sticker for my JRSC and then the guy didn't even notice the supercharger.
I guess I had an easier time passing visual. The guy popped my hood and came face to face with $6k of aftermarket parts. He kind of looked confused then said "I don't even want to mess with this stuff." Lol. Then he shut the hood and that was it.
He was so dumb he didn't even notice the supercharger because when I was leaving he's like "you need more than just bolt-ons, you should get a turbo." I just played along and was like "yeah, I'll put a turbo on soon." It actually kind of sucked because I spent $30 buying the CARB sticker for my JRSC and then the guy didn't even notice the supercharger.
#36
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Re: I finally did it!!! Knock sensor bypass!! Woot! Woot! (EnzoSpeed)
I wish it was that easy for me... These guys were pretty cool and all, they just coverd everything in my engine bay. Had the test almost beat, but in the last 2 minutes literally I threw a CEL code 23. It won't happen this time, and I can finally get my stupid BAR sticker.... This is why I hate Cali.
Thanks again for the help.
Thanks again for the help.
#40
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Re: (JRciv)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JRciv »</TD></TR><TR><TD CLASS="quote">**UPDATE**
Well I finally got around to passing smog. As you know, you must log mileage into your ECU after it is reset otherwise you can't pas smog. After first installing the transducer, I drove around for a few days and my CEL came on at 50 miles. I reset the ECU and drove around for a few more days and the CEL came on again at 70 miles. I figured out that it was coming back on because my transducer was not making enough voltage and the ECU was realizing my hack.
So what I finally had to do was drive more agressively. Shift at higher RPMs and stay in fourth gear more often (not fifth). This increased the engine vibration which kept the transducer working. I drove around like this for about a week and no CEL. I was able to log 100 miles with no CEL and could finally smog it.
</TD></TR></TABLE>
wouldn't running a second piezo solve this problem?
Well I finally got around to passing smog. As you know, you must log mileage into your ECU after it is reset otherwise you can't pas smog. After first installing the transducer, I drove around for a few days and my CEL came on at 50 miles. I reset the ECU and drove around for a few more days and the CEL came on again at 70 miles. I figured out that it was coming back on because my transducer was not making enough voltage and the ECU was realizing my hack.
So what I finally had to do was drive more agressively. Shift at higher RPMs and stay in fourth gear more often (not fifth). This increased the engine vibration which kept the transducer working. I drove around like this for about a week and no CEL. I was able to log 100 miles with no CEL and could finally smog it.
</TD></TR></TABLE>
wouldn't running a second piezo solve this problem?
#41
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Re: (D16A6_HF)
back from the dead
If u need to wire to piezo's together u wire them negative to positive to negative to positive using both ends one positive and one negative right. or both neg's together and both posi's together? iam getting a cel still both ways but i have them tight together would it be better lose and separated?
If u need to wire to piezo's together u wire them negative to positive to negative to positive using both ends one positive and one negative right. or both neg's together and both posi's together? iam getting a cel still both ways but i have them tight together would it be better lose and separated?
#42
Re: Re: (pelon 1990 civic si)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by pelon 1990 civic si »</TD></TR><TR><TD CLASS="quote">do a d16z6 comess with knock sensor</TD></TR></TABLE>
nope
nope
#45
Re: I finally did it!!! Knock sensor bypass!! Woot! Woot! (JRciv)
For those who doesnt want to bypass their Knock sensor, heres a tip that works.
This is for those who have a working knock sensor.
1. Cut the plug from the harness leaving a little wire left for the connection. (about 1 inch)
2. Take a RCA wire. In a RCA wire there are two wires. Outer and Inner. Strip the end and pull back the outer wires away from the inside wire.
3. strip the inside wire and connect it to the plug. Tape it with Electrical tape push back the outer wires over the taped part and tape over it agian.
4. Cover it with plastic from the harness. or you can use any plastic wire cover which you can buy at any store that sales wire stuff (dont forget to plug it to the knock sensor after your done.)
5. Slice the other end the same way as step 2, and follow step 3 agian but this time plug it to the ecu.
6. Next ground the outer wire from the ECU side to the chassie and your done.
(Important- Make sure the outer and inner wire does not touch each other)
This should solve any Working Knock sensor problem.
Good Luck!
This is for those who have a working knock sensor.
1. Cut the plug from the harness leaving a little wire left for the connection. (about 1 inch)
2. Take a RCA wire. In a RCA wire there are two wires. Outer and Inner. Strip the end and pull back the outer wires away from the inside wire.
3. strip the inside wire and connect it to the plug. Tape it with Electrical tape push back the outer wires over the taped part and tape over it agian.
4. Cover it with plastic from the harness. or you can use any plastic wire cover which you can buy at any store that sales wire stuff (dont forget to plug it to the knock sensor after your done.)
5. Slice the other end the same way as step 2, and follow step 3 agian but this time plug it to the ecu.
6. Next ground the outer wire from the ECU side to the chassie and your done.
(Important- Make sure the outer and inner wire does not touch each other)
This should solve any Working Knock sensor problem.
Good Luck!
#46
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Re: I finally did it!!! Knock sensor bypass!! Woot! Woot! (JRciv)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JRciv »</TD></TR><TR><TD CLASS="quote">Man, it feels so good getting rid of that CEL. Now I can pass smog!
So if anyone ever needs to bypass their knock sensor without tripping a CEL, here is what you need to know.
First of all, you can't ground it out or replace it with a resistor. The knock sensor is not an electrical load, it actually produces it's own voltage. Your ECU is looking for a variable voltage from the sensor.
So what you want to do is mimic the voltage output. Here is a guide of what to do:
1. First, go to Radioshack and buy a piezo transducer, part #273-073. You will find it will all the buzzers because that it's intended for. It costs $1.99.
2. Flip to the back of your haynes and look at the chassis electrical pages. Find which wire going into your ECU is for the knock sensor. If you have a 96-00 civic, it is the Red wire with a blue stripe. MAKE SURE YOU DON'T MISTAKE IT FOR THE BLUE WIRE WITH A RED STRIPE. That's for your AC system. Cut the wire about 6" from the ECU.
3. Tape the transducer to your fuel rail.
3. Weave a single wire from your fuel rail back to your ECU.
4. Connect the speaker wire to the (+) wire on the transducer.
5. Connect the other end of the wire to the Red/blue wire on your ECU.
6. Connect the (-) wire on the transducer to a good ground.
So basically, the positive wire of the transducer goes to the ECU and the negative wire goes to ground. I taped the transducer to the fuel rail because that's where I found it made the most voltage (most vibration).
The transducer only makes about a half a volt at 4k rpms and the ECU usually sees about 1.5 volts. So if you try this and it doesn't work, you will have to find a better location to tape the transducer or you will have to add a second transducer to bump up the voltage.</TD></TR></TABLE>
hey on step 4 it says use the speaker wire and connect it to the transducer +.. Can i just connect the red blue wire from my ecu straight to the transducer and skip the speaker wire.?
THanx
Thanks
So if anyone ever needs to bypass their knock sensor without tripping a CEL, here is what you need to know.
First of all, you can't ground it out or replace it with a resistor. The knock sensor is not an electrical load, it actually produces it's own voltage. Your ECU is looking for a variable voltage from the sensor.
So what you want to do is mimic the voltage output. Here is a guide of what to do:
1. First, go to Radioshack and buy a piezo transducer, part #273-073. You will find it will all the buzzers because that it's intended for. It costs $1.99.
2. Flip to the back of your haynes and look at the chassis electrical pages. Find which wire going into your ECU is for the knock sensor. If you have a 96-00 civic, it is the Red wire with a blue stripe. MAKE SURE YOU DON'T MISTAKE IT FOR THE BLUE WIRE WITH A RED STRIPE. That's for your AC system. Cut the wire about 6" from the ECU.
3. Tape the transducer to your fuel rail.
3. Weave a single wire from your fuel rail back to your ECU.
4. Connect the speaker wire to the (+) wire on the transducer.
5. Connect the other end of the wire to the Red/blue wire on your ECU.
6. Connect the (-) wire on the transducer to a good ground.
So basically, the positive wire of the transducer goes to the ECU and the negative wire goes to ground. I taped the transducer to the fuel rail because that's where I found it made the most voltage (most vibration).
The transducer only makes about a half a volt at 4k rpms and the ECU usually sees about 1.5 volts. So if you try this and it doesn't work, you will have to find a better location to tape the transducer or you will have to add a second transducer to bump up the voltage.</TD></TR></TABLE>
hey on step 4 it says use the speaker wire and connect it to the transducer +.. Can i just connect the red blue wire from my ecu straight to the transducer and skip the speaker wire.?
THanx
Thanks
#48
Re: I finally did it!!! Knock sensor bypass!! Woot! Woot! (GSRWSU)
Yeah i dont get the speaker wire thing either... Does it splice into 2 locations? So it connects to the cd player system or what? i am totally lost at that point
#49
Re: I finally did it!!! Knock sensor bypass!! Woot! Woot! (VNTEC)
Holy crap, this thread has been getting bumped? I forgot that it mysteriously doesn't show up as a "recent topic" anymore.
Anyway, I did this ages ago, so I'll try to remember what I did... You could just use the stock knock sensor wire instead of the speaker wire. I think I used the speaker wire because it was easy to t-tap into the harness rather than cut off the sensor end. That way, you won't have to re-solder the end back on if you ever want to use a knock sensor.
That's my guess. I don't know. All you need to know is this: the positive end of the transducer needs to be fed into the knock sensor input at the ECU, and the negative end of the transducer needs to be connected to ground. That's it. I probably over-complicated the directions.
Also, the way to increase the voltage would be to wire the transducers in series. That is:
But that is not necessary. Just keep moving the single transducer around until you find a location that produces enough vibration and noise. Everyone else has been able to do it with only one. Also, secure the transducer LOOSELY. That's what worked the best for me because the transducer would bounce around on the fuel rail.
Modified by EnzoSpeed at 1:17 AM 1/5/2006
Anyway, I did this ages ago, so I'll try to remember what I did... You could just use the stock knock sensor wire instead of the speaker wire. I think I used the speaker wire because it was easy to t-tap into the harness rather than cut off the sensor end. That way, you won't have to re-solder the end back on if you ever want to use a knock sensor.
That's my guess. I don't know. All you need to know is this: the positive end of the transducer needs to be fed into the knock sensor input at the ECU, and the negative end of the transducer needs to be connected to ground. That's it. I probably over-complicated the directions.
Also, the way to increase the voltage would be to wire the transducers in series. That is:
But that is not necessary. Just keep moving the single transducer around until you find a location that produces enough vibration and noise. Everyone else has been able to do it with only one. Also, secure the transducer LOOSELY. That's what worked the best for me because the transducer would bounce around on the fuel rail.
Modified by EnzoSpeed at 1:17 AM 1/5/2006
#50
Re: I finally did it!!! Knock sensor bypass!! Woot! Woot! (EnzoSpeed)
good post i was hoping this was possible.
why not just leave the ecu out of it, and cut the knock sensor's plug off in the engine bay, wire the transducer to it there, and ground it somewhere on the block. would that work?
also i have those jimfab mounts with poly bushings, could that be too much vibration? i'm hoping it's just enough so that i can put it anywhere.
why not just leave the ecu out of it, and cut the knock sensor's plug off in the engine bay, wire the transducer to it there, and ground it somewhere on the block. would that work?
also i have those jimfab mounts with poly bushings, could that be too much vibration? i'm hoping it's just enough so that i can put it anywhere.