Mike "Wuzzy121". Rest in peace, brother

Go Back   Tacoma World Forums > Tacoma Discussion > 1st Gen. Tacomas

Notices

Rear O2 sensor bypass/CEL fix.

Reply
 
Thread Tools Search this Thread
Old 04-17-2014, 09:53 AM   #1
Mod [OP] Mod is online now
Senior Member
Mod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shed
Joined: Jul 2010, #40950
Location: CR, WA
Gender: Male
Posts: 1,222
Mod's Tacoma Gallery
Rear O2 sensor bypass/CEL fix.

First off want to say that someone else figured this out,not my idea, but it was too good to not share on here. Back in about 04-05 I had my catalytic converter sawzall'd off and stolen. On comes the check engine light. Didn't think to much about the light being on because I knew what it was after a very short period of time. Climbing a steep grade with a load and putting more heat on the system, the light would go off. Once crested the hill and things started to cool off,,the light would come back on. Rear O2 sensor sending the signal that something was amiss. Truck never gave me any problems so no need to by a code scanner and I knew what the CEL light was from. (For the sake of arguments, lets say I had a really good idea why the light was on). Anyways,,here we go.





Radio Shack part #
1 micro farad cap 272-1055
1 mega ohm resistors 271-1134

On my truck there are 4 wires that lead to that rear O2 sensor from the connection plug at the manual transmission tail shaft. 2 black and a sold white and solid blue I split the distance in the length of those blue and white wires and cut them in two at the center. You will probably have to pull back or remove the tubing/covering that covers those wires. I slit that cover down the center with a razor to about 1/2 distance, then cut around it, removing that portion. Snip and strip back the blue and the white wire that leads forward to the connection plug,,I left the two black wires intact and connected to the sensor. The reason I cut the blue and white wires at equal lengths between connection plug and sensor,,was so that they could be easily reconnected again if needed.

As you see the pic above of the constructed Mod unit(),,the right side of the unit connects to the blue wire you cut and stripped back a 1/2",,and the left connects to the white wire that you also prepared the same way. (connection plug side)

Assemble the unit as you see in the pic noticing lettering up on the blue capacitor and color rings on the resistor. Right side of assembled unit connects to the blue wire, and the left side of above pic connects to the white wire.

You can solder connections if you wish, or you can crimp connect so long as you have good crimping tools and supplys. I did a little of both. A bead of silver solder was melted by iron down into the bottoms of those crimp connectors you see above. The unit was then crimped and soldered to the prepared blue and white wires down by the sensor that lead to the plug connection

Snipped white and blue wires leading to the sensor were covered with heat shrink tube. I didn't pull any connection plug or the sensor out of the pipe,no real need because I had the wire length I needed.

Total cost to turn out the check engine light due to a rear O2 sensor code,,about $4.

Pull battery connections BEFORE you start cutting. Not a bold typed set in stone rule,,but It's the way I did it. The ECU will need a reset anyways after doing the work.

I'm no electronics expert so keep the questions with that in mind.
  Reply With Quote
Old 04-17-2014, 09:58 AM   #2
Senior Member
Redneck92 is one of the sharper tools in the shedRedneck92 is one of the sharper tools in the shedRedneck92 is one of the sharper tools in the shedRedneck92 is one of the sharper tools in the shedRedneck92 is one of the sharper tools in the shedRedneck92 is one of the sharper tools in the shedRedneck92 is one of the sharper tools in the shedRedneck92 is one of the sharper tools in the shedRedneck92 is one of the sharper tools in the shedRedneck92 is one of the sharper tools in the shedRedneck92 is one of the sharper tools in the shed
 
Redneck92's Avatar
Name: Chris
Joined: Aug 2012, #84398
Location: Concord, NC
Age: 22
Gender: Male
Posts: 1,292
Redneck92's Tacoma Gallery
Good stuff. Might end up going this route.
  Reply With Quote
Old 04-17-2014, 10:20 AM   #3
Mod [OP] Mod is online now
Senior Member
Mod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shed
Joined: Jul 2010, #40950
Location: CR, WA
Gender: Male
Posts: 1,222
Mod's Tacoma Gallery
Thanks. It's really easy and cheap and you can re connect those wires if needed.

If the CEL light stays lit after doing this, then you might have another code waiting to be read.
  Reply With Quote
Old 04-17-2014, 08:29 PM   #4
Mod [OP] Mod is online now
Senior Member
Mod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shed
Joined: Jul 2010, #40950
Location: CR, WA
Gender: Male
Posts: 1,222
Mod's Tacoma Gallery
About 4 days on this,,so far no light.
  Reply With Quote
Old 04-24-2014, 06:20 PM   #6
Mod [OP] Mod is online now
Senior Member
Mod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shed
Joined: Jul 2010, #40950
Location: CR, WA
Gender: Male
Posts: 1,222
Mod's Tacoma Gallery
Rock auto shows a 4 wire heated sensor,,so I think it would work. Can't say for positive because mine is manual. The part numbers don't match between yours and mine on the sensor.

Easy to slit the covering/insulation that covers the wires to the sensor and see if you have 2 black, a white and blue wire. So long as that sensor wasn't mashed heavy on the rocks, and the heated circuit on it is still good.

After some more fine print reading, I am leaning twoards that heated circuit being intact and doing it's thing at the sensor.

So far, no CEL and damned if it didn't help the idle/warmup. I am idling down in about 45sec, compared to a full minute. Might be the season change.

$4 in one hand,,and a whole bunch in the other to fix it. Pretty easy choice or check.

If you give it a shot, please say so and the outcome. Thanks all.
  Reply With Quote
Old 06-24-2014, 11:24 AM   #7
Member
dan476 is on a distinguished road
Joined: Apr 2012, #77390
Gender: Male
Posts: 45
dan476's Tacoma Gallery
Hey, you mentioned that someone else figured this out, do you by any chance have original link? Also how is it working now? Any fuel mileage increase? Thanks.
  Reply With Quote
Old 06-24-2014, 03:45 PM   #8
raise hell, drink beer
mustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shed
 
mustangstephen's Avatar
Name: Stephen
Joined: Oct 2013, #114510
Location: by da creek
Gender: Male
Posts: 669
mustangstephen's Tacoma Gallery
I did this and didn't have any luck. Maybe someone can point out where I went wrong? FWIW I got the URD sim kit and haven't had a problem since.

And yes I taped everything up after this.

  Reply With Quote
Old 06-24-2014, 04:28 PM   #9
Senior Member
ssanders2211 is one of the sharper tools in the shedssanders2211 is one of the sharper tools in the shedssanders2211 is one of the sharper tools in the shedssanders2211 is one of the sharper tools in the shedssanders2211 is one of the sharper tools in the shedssanders2211 is one of the sharper tools in the shedssanders2211 is one of the sharper tools in the shedssanders2211 is one of the sharper tools in the shedssanders2211 is one of the sharper tools in the shedssanders2211 is one of the sharper tools in the shedssanders2211 is one of the sharper tools in the shed
Joined: Jan 2014, #121976
Location: Midwest
Gender: Male
Posts: 173
ssanders2211's Tacoma Gallery
sub'd
  Reply With Quote
Old 06-25-2014, 06:29 AM   #10
Member
dan476 is on a distinguished road
Joined: Apr 2012, #77390
Gender: Male
Posts: 45
dan476's Tacoma Gallery
After doing some research I'm seeing that capacitor goes between blue and white wire, resistor thought has to be on blue only below the capacitor. That could be your issue.
  Reply With Quote
Old 06-25-2014, 07:19 AM   #11
raise hell, drink beer
mustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shedmustangstephen is one of the sharper tools in the shed
 
mustangstephen's Avatar
Name: Stephen
Joined: Oct 2013, #114510
Location: by da creek
Gender: Male
Posts: 669
mustangstephen's Tacoma Gallery
Quote:
Originally Posted by dan476 View Post
After doing some research I'm seeing that capacitor goes between blue and white wire, resistor thought has to be on blue only below the capacitor. That could be your issue.
:shrug: I've had the URD sim in for over a year now. I'm not going to pull it out and try anything else. Just figured I'd share my experience.
  Reply With Quote
Old 07-05-2014, 09:02 AM   #12
Mod [OP] Mod is online now
Senior Member
Mod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shed
Joined: Jul 2010, #40950
Location: CR, WA
Gender: Male
Posts: 1,222
Mod's Tacoma Gallery
Stephen, did you unplug the URD sim from the system before the adaptation for the radio shack stuff?. Never had one of those so I don't know where they plug in at.



I disco'd the radio shack setup, just to see if it kicked the cel light back on,,and it did as I kinda knew it would. Reconnected that and reset the ECM, light went out once again.
  Reply With Quote
Old 07-05-2014, 02:10 PM   #13
Member
mech160 is on a distinguished road
Joined: Oct 2011, #65675
Location: 50th
Gender: Male
Posts: 36
mech160's Tacoma Gallery
sub'd
  Reply With Quote
Old 07-06-2014, 06:45 PM   #14
Senior Member
Robb235 is on a distinguished road
 
Robb235's Avatar
Joined: Sep 2013, #112091
Location: Chattanooga, TN
Gender: Male
Posts: 129
Robb235's Tacoma Gallery
May have to try this on my 4Runner. I've got the dreaded P0420 coded that I've pretty much ignored for 2 years.
  Reply With Quote
Old 07-23-2014, 01:13 PM   #17
Mod [OP] Mod is online now
Senior Member
Mod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shedMod is one of the sharper tools in the shed
Joined: Jul 2010, #40950
Location: CR, WA
Gender: Male
Posts: 1,222
Mod's Tacoma Gallery
Quote:
Originally Posted by thekidcatcher View Post
Dang it, its only 1st gen isn't it.
Pimpin my own thread,,to keep it at the top unashamedly.

It might work with a 2nd gen,, but cant verify. A few bucks and some time is all it takes. Work smart and it a easy reversal if needed.

No codes or cel so far, still truckin along.
  Reply With Quote
Old 07-23-2014, 04:53 PM   #18
Senior Member
BlackSportD has much to be proud ofBlackSportD has much to be proud ofBlackSportD has much to be proud ofBlackSportD has much to be proud ofBlackSportD has much to be proud ofBlackSportD has much to be proud ofBlackSportD has much to be proud ofBlackSportD has much to be proud ofBlackSportD has much to be proud of
Navy: EM1 Coastal Warfare
Joined: Aug 2007, #2299
Location: Los Angeles
Gender: Male
Posts: 342
BlackSportD's Tacoma Gallery
Send a message via AIM to BlackSportD
I'd be curious to see air fuels. The rear narrowband o2 sensor is used not just for cat efficiency, but to calibrate the forward primary wideband sensor on 01+ Trucks and 98 or something 4runners. That means if the solid state components are not finely selected, IMO it may be able to pass you on your cat diagnostics, but could be throwing off air fuels a bit.
  Reply With Quote
Old 07-24-2014, 01:55 PM   #19
Senior Member
Yoda the Taco is on a distinguished road
 
Yoda the Taco's Avatar
Name: Chase
Joined: Feb 2014, #122988
Location: Kingsport
Gender: Male
Posts: 167
Yoda the Taco's Tacoma Gallery
Mod
Dumb question, but is it the blue wire that needs to go on the red stripped side of the resistor? My brain is fried from work, so I just wanted to ensure before I give it a go. Also, any noticeable loss or gain of MPG? Thanks
  Reply With Quote
Old 07-24-2014, 01:58 PM   #20
Senior Member
Robb235 is on a distinguished road
 
Robb235's Avatar
Joined: Sep 2013, #112091
Location: Chattanooga, TN
Gender: Male
Posts: 129
Robb235's Tacoma Gallery
Quote:
Originally Posted by BlackSportD View Post
I'd be curious to see air fuels. The rear narrowband o2 sensor is used not just for cat efficiency, but to calibrate the forward primary wideband sensor on 01+ Trucks and 98 or something 4runners. That means if the solid state components are not finely selected, IMO it may be able to pass you on your cat diagnostics, but could be throwing off air fuels a bit.
Never heard of this before. I've always heard that the rear O2 did not have any bearing on fuel trims.
  Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
O2 sensor help and cel codes mrman 1st Gen. Tacomas 11 07-29-2013 10:05 PM
O2 Sensor CEL ALL! takaya49 2nd Gen. Tacomas 6 05-03-2012 08:53 PM
Help needed for a live reading of rear o2 sensor (bank 1 sensor 2) geoff06 Technical Chat 7 11-30-2011 05:57 AM
URD Rear O2 Simulator 4.0L V6 CEL FIX!! FOR SALE!! turbo222 Buy / Sell / Trade 9 04-07-2010 07:30 AM
3.4 coil packs, rear O2 sensor, water temp sensor glassdoc Buy / Sell / Trade 6 01-28-2009 07:51 AM


Copyright © 2015 Tacoma Forum. Tacoma World is not owned by, or affiliated with Toyota Motor Corporation.