Make Your Own O2 Sensor Eliminators

[Guest kerplode]

Yes, it IS correct for the PCII, which is what I was addressing.

<{POST_SNAPBACK}>

Okay...Sorry. I assumed PCIII, which is the only PC I've had FHE with.

[Trace]

Yeah, I guess we should be very specific with what PC version we're talking about. And I'm begining to suspect that it might apply to the "no-PC, no O2, yes O2" issue, too.

FWIW, I had better luck with the 98/99 maps on my 2000 than the 00/01 maps. I ended up using the 98/99 version for my baseline. Of course, I have no cat and no O2s, either.

[sunline]

Hmm, interesting, I am running PCll with full system; no cat, no o2 etc. All I did was take the o2 sensors and zip them to the bottom of the bike. Still plugged in just hanging basically from the bottom of the engine. Dont remember exactly where I tied em off to but it has worked fine for 35000 miles. 107 rear wheel hp on Mike Velascos dyno. Used a micron map for 92 octane gas that was on dynojet website. That was the best one we found for mix and power after a number of dyno runs. Mike said no problem hanging the o2 gizmos and never has been one.

[Stéphane]

If I understand well, the resistance should have these colours bands in that order: orange, orange, brown and gold (or silver).

Here's a link to read to colour coding: http://xtronics.com/kits/rcode.htm

[Guest Jaguarjoe007]

Hey cozye,

Had the resistors installed properly and the code for them is gone. One problem is the Fi light still came on, first very light and then brighter and brighter. Then noticed that it blinks with the turn signals, gets bright with the brake, horn etc, so have a short somewhere on the ground side. Most likely a loose connection. Will hunt for it this weekend. It quit stalling out when warm, so the puter must like the resistors. Thanks for the help.

[cozye]

Hey cozye,

Had the resistors installed properly and the code for them is gone.  One problem is the Fi light still came on, first very light and then brighter and brighter.  Then noticed that it blinks with the turn signals, gets bright with the brake, horn etc, so have a short somewhere on the ground side.  Most likely a loose connection.  Will hunt for it this weekend.  It quit stalling out when warm, so the puter must like the resistors.  Thanks for the help.

<{POST_SNAPBACK}>

Hey,

No prob. Glad I could help. Hope you find that loose connection.

Good luck.

[enzed_viffer]

I installed some resistors when I had a borrowed PCII to try out on my 2001 VFR. When I returned the PCII, I left the resistors in, as I did not like the lean surging and open loop/closed loop transition I had with the O2 sensors connected. Now the bike doesn't run perfectly below 5000 rpm, but I feel it's definitely better than with the sensors connected.

YMMV....

EDIT: Looking at the PC map that worked best for me, it seems that my bike may now be running a little lean at 2-5% throttle below 5.5K rpm, without the PC to correct for this.

Edited April 18, 2006 by enzed_viffer

[CornerCarver]

So, for a 2001 I should just get a PCII to go with a 98-99 exhaust, and eliminate the O2 sensors? I just recieved the PCIII USB that i ordered. Now I hear that the PCII lets me have control of more than just fuel input...

:blink:

[Guest scottfair2003]

Finally figured it out (without breaking it!) and got my resistors and PC III installed. Loaded up BenSV's map and WOW!!! A different motorcycle. No more herky jerky at low speeds and no more dreading the VTEC kick-in. It's raining like heck today, so I only did about 10 miles to check it out. Thanks to all who contribute here.

Julie

Hi. I am new to the forum and new to the VFR but not at all new to bikes. I found the cheapest solution for the loss of power in the 5k range at constant throttle.............twist it a little bit more and keep it up in Vtec mode! If its too fast try a lower gear.......free and seems to work well for me! :idea3: I have been trying to make sure that I remain in the vtec for as long as possible.....red line means shift now right? hehehe ( I actually have found that 10,500 or so is a good shift point to stay in vtech mode and not have the power drop off at any given point. I dont think this is at all harmful to the motor but it may be harmful on the wallet if the price of gas goes up......now that I think about it I may invest the 30 bucks :wheel:

[Guest vf'er]

Now, its my turn. I have had my vfr for a year and a half. Now starting to make mods. Just ordered a FPR for it today. Plan on putting in a PC11 and and after market exhaust later and make cat mods. Will the FPR change any of my plans? :blink:

[Darth Bling]

Hi. I am new to the forum and new to the VFR but not at all new to bikes. I found the cheapest solution for the loss of power in the 5k range at constant throttle.............twist it a little bit more and keep it up in Vtec mode! If its too fast try a lower gear.......free and seems to work well for me! :idea3:

Free?! What about all the extra gas you burn up? Besides, I don't think running down the freeway at 8000 rpm is the most fuel efficient way to travel. It's a great idea if you're tearing it up in the twisties. :thumbsup:

Besides that, 330 ohm resistors are only 99?. That's probably way cheaper than a 5-10 mpg penalty to your fuel mileage when running 7k+ rpms.

[Guest EV]

So 330 ohm resistance OK

the guy at the shop asked me what wattage, what is it?

[cozye]

So 330 ohm resistance OK

the guy at the shop asked me what wattage, what is it?

very low wattage. 1/2 watt will be fine. Any of them you get will be fine. The 1/2 watt ones have a thicker lead than the 1/4 watt, a little more secure when you bend them over and stick them in the plug. The lead size is probably more important than the wattage in this case.

[didit]

This may be too obvious for most, but I need to ask.

Once you have installed the 330 ohm resistors, can you remove the opposite plug ends right down to the pipes?

I beleive I read once on a lost thread, that you can plug off where the sensors tap into the pipes, before the cat.

Is this true? If so, what might one suggest is the best plugging method (if other than just a suitable bolt)?

[Guest 767fixer]

This may be too obvious for most, but I need to ask.

Once you have installed the 330 ohm resistors, can you remove the opposite plug ends right down to the pipes?

I beleive I read once on a lost thread, that you can plug off where the sensors tap into the pipes, before the cat.

Is this true? If so, what might one suggest is the best plugging method (if other than just a suitable bolt)?

you can delete those leads as they go directly to the 02 sensors. but i wouldnt just cut them off. id remove the sensors like you mention. they make special plugs to fill the space where the sensor was. the sensor looks to be near the same size as a car version, so a performance shop may be a place to locate said plugs.

[didit]

Thank you.

I'll let you know what I find.

Really appreciate the guidance.

[cozye]

Thank you.

I'll let you know what I find.

Really appreciate the guidance.

I believe it was 18MM drain plugs from Autozone and some copper washers that worked for me. Just take one of the sensors with you and match up the threads.

[turtlecreek]

Thank you.

I'll let you know what I find.

Really appreciate the guidance.

I believe it was 18MM drain plugs from Autozone and some copper washers that worked for me. Just take one of the sensors with you and match up the threads.

did this today. NAPA PART # 704-1037 18mm x 1.5 Drain Plug fits right in!

[custompcs37421]

I have a 2006 and the right side of my bike is totally diffrent from the picture below. I can't find the o2 senser plugs to install this mod. Could someone post a picture or point me in the right direction.

Edited May 26, 2007 by custompcs37421

[turtlecreek]

all this is on the left side.

[Guest Johnny Diablo]

Thanks for the "how to" Finally did it today and made the FI light go out. I was getting the 4k stumble under hard acceleration with my pc3. Changed the oil too.

[Guest tjvfr800]

However, I discovered that by turning the ignition on, letting it go through it's whine, then turn it off and then back on and then start the engine, the surging and flat spot are completely eliminated. Why does this happen? No f ing clue. Some think that the computer resets itself after you shut down the bike each time. By "rebooting" the computer it seems to read the open loop. I think Das Bone has documented this too. So leave them in and just on/off/on your bike each time. Beats spending 300 bucks on a PC111.

I have tried this and this really works, the bike feels and sounds a lot smoother but a flatspot betwen 4k-5k rmp , but why !!! Any one got a clue why it's possible to do this with the ECU. Is there any hidden test modes to set up the ECU in, or perhaps some feature that don't got to the consumer lines.

And for the "I think Das Bone has documented this too" can't find it, can you give me any directions ... :unsure:

!! parden my english it's not my native language !!

[Darth Bling]

I have tried this and this really works, the bike feels and sounds a lot smoother but a flatspot betwen 4k-5k rmp , but why !!! Any one got a clue why it's possible to do this with the ECU. Is there any hidden test modes to set up the ECU in, or perhaps some feature that don't got to the consumer lines.

And for the "I think Das Bone has documented this too" can't find it, can you give me any directions ... :goofy:

!! parden my english it's not my native language !!

From another post that I posted yesterday:

Apparently the ECU isn't fooled by the O2-eliminator mod and when it enters closed loop mode, it tries to adjust the air/fuel ratio. Unfortunately, any adjustments the ECU makes won’t register because the O2-eliminators are sending a constant signal to the computer. So the ECU continues to adjusts the air/fuel mixture in a vain attempt to reach the stoichiometric ratio and it eventually leans out the air/fuel mixture so much that the engine loses a ton of power. When you twist the throttle a bit, the ECU leaves closed loop mode and goes back to the default map. The engine suddenly makes power again and the bike lurches violently forward.

Ironically, the O2-eliminators are suppose to make the ECU think everything as just fine when it enters closed loop mode, but it instead has cause some bikes to surge severely.

The trick around this is to prevent the bike from entering closed loop mode. This can be achieved by starting the bike before the ECU has a chance to complete its boot up cycle.

Now, when you turn the ignition on, you see the digital gauges flash on once and then display normally. I believe this is caused by the ECU going though a boot up cycle. If you start the bike before the ECU finishes its boot up cycle, then it won’t go into closed loop later. My guess is that by starting the bike before the ECU boots up causes an error in the ECU. To protect the bike, the ECU loads the default map and sticks with it. So, once you turn the ignition on, start your bike immediately and you shouldn’t have any more surging issues. (Likewise, there’s no reason this wouldn’t work for bikes without O2-eliminators either).

This is my start up procedure (which seems to work very well to avoid this surging problem):

1) Turn ignition on.

2) Put the bike into neutral.

3) Wait for the fuel pump to prime the fuel system.

4) Once FI system is primed, then in quick secession: turn ignition off, push the starter button, turn ignition on, release starter once bike starts.

[Guest tjvfr800]

I have tried this and this really works, the bike feels and sounds a lot smoother but a flatspot betwen 4k-5k rmp , but why !!! Any one got a clue why it's possible to do this with the ECU. Is there any hidden test modes to set up the ECU in, or perhaps some feature that don't got to the consumer lines.

And for the "I think Das Bone has documented this too" can't find it, can you give me any directions ... :unsure:

!! parden my english it's not my native language !!

From another post that I posted yesterday:

Apparently the ECU isn't fooled by the O2-eliminator mod and when it enters closed loop mode, it tries to adjust the air/fuel ratio. Unfortunately, any adjustments the ECU makes won’t register because the O2-eliminators are sending a constant signal to the computer. So the ECU continues to adjusts the air/fuel mixture in a vain attempt to reach the stoichiometric ratio and it eventually leans out the air/fuel mixture so much that the engine loses a ton of power. When you twist the throttle a bit, the ECU leaves closed loop mode and goes back to the default map. The engine suddenly makes power again and the bike lurches violently forward.

Ironically, the O2-eliminators are suppose to make the ECU think everything as just fine when it enters closed loop mode, but it instead has cause some bikes to surge severely.

The trick around this is to prevent the bike from entering closed loop mode. This can be achieved by starting the bike before the ECU has a chance to complete its boot up cycle.

Now, when you turn the ignition on, you see the digital gauges flash on once and then display normally. I believe this is caused by the ECU going though a boot up cycle. If you start the bike before the ECU finishes its boot up cycle, then it won’t go into closed loop later. My guess is that by starting the bike before the ECU boots up causes an error in the ECU. To protect the bike, the ECU loads the default map and sticks with it. So, once you turn the ignition on, start your bike immediately and you shouldn’t have any more surging issues. (Likewise, there’s no reason this wouldn’t work for bikes without O2-eliminators either).

This is my start up procedure (which seems to work very well to avoid this surging problem):

1) Turn ignition on.

2) Put the bike into neutral.

3) Wait for the fuel pump to prime the fuel system.

4) Once FI system is primed, then in quick secession: turn ignition off, push the starter button, turn ignition on, release starter once bike starts.

Thanks for great startup tip, my bike is totally stock and don't have any O2 elims. And this on / off / on thing still makes the bike feel much better than after an normal start.

[Guest Capflamme]

Hello everyone!

I don't have a VFR but a CBR 1000rr (2006). The bike has an o2 sensor (narrow band) and would like to get ride of it to install an air/fuel ratio based engine tuner with a wideband o2 sensor. If I understand well the 15$ o2 sensor eliminator kit from dynojet is just a 330omh resistor put between the correct 2 pins on the harness side of the o2 sensor connector. As the stock o2 sensor connector on my bike is different from the one depicted in this topic, I would like to know between which wires I have to put the resistor. Basically what is the colors of the wires connected by the resistors. I know that zirconium o2 sensor have 4 wires which are signal/ground/heater(+)/heater(-). Which ones should I connect together with the resistors. It's not very clear from the pictures...

Thanx in advance for the help!

:rolleyes:

Edited February 28, 2008 by Capflamme