My cel came on.(p0137) I changed the secondary o2 sensor and the cel persisted after resetting the ecu. I installed an o2 simulator to help me diagnose and the cel came on after a week, giving me a p0420 (bac cat).

The simulator should be fooling the ecu into getting a proper signal from the sensor.
Does this mean I have a wiring problem somewhere between the ecu and the sensor? Any help will be greatly appreciated, thank you.

 

maybe your cat is no longer cleaning the air like it should be. and thats what caused your O2 sensor code. happens all the time in these cars , instead of getting a code for what the problem is , whatever is causing the problem sets off another sensor.

 

which O2 simulator did you install?
did you include the heater resistor with the simulator?
where did you install it?

 

no need for a simulator...just use a plug fowler...any store has them and this allows for limited space around the o2 sensor.....this makes it read less

 

I installed a simulator for the sensor after the cat. The original code was p0137 (secondary sensor, low volt). After I installed the simulator I got a p0420 (cat below treshold efficiency).

I don't want to buy an expensive cat and the problem turning out to be a shorted wire, or something of that sort.

 

I installed the simulator to the signal and the ground wires of the sensor, like the instructions said. The cel went away for a week and came up again with the p0420.

I would think that if the simulator eliminated the cel permanently, that would rule out things like an exhaust manifold leak, or a bad catalytic converter. Since the simulator is is not working, I'm guessing like the signal wire is shorted to ground. I'm thinking installing new wires from the ecu to the sensor.

A new cat is like 200 or 300 bucks. I might go with a stainless steel ebay header and a magnaflow cat, but I would rather go stock since I want my Civic to last me ten more years.

 

secondary O2 trick
remove secondary O2, plug secondary O2 sensor hole in exhaust. do what ever you want with the cat.
wire O2 simulator in at the ECU.
wire in one 1kohm 1watt resistor between the secondary O2 heater control line and switch 12V.

the simulators operation is simple, but it really depends one which O2 simulator you have. If it produces too much signal, or not enough signal you will get a CEL.

I've used this setup many times with zero problems... http://www.mkiv.com/techarticl...lator

 

Hey Relic1, i got all those things from Radio Shack.... BUT, i had a problem getting the R1, R2, R3, R4 because i dont know the voltage i need, i needed to know if it was 1/4w or 1/2w or 1w, i wish the part number was on the link you showed, very good help though, thanx and another thing, is all this ok to do on my obd2 civic? cause i notice the page is for toyota

 

There is a MIL eliminator that you can get off of eBay for $7...thats what I got and its been working great.

 

Your saying i can use this mil eliminator instead of building this board? if i get this instead, u think i can pass an inspection?

 

I'm getting a P0141 O2 Sensor Heater Circuit Malfunction. Will a Mil Eliminator work to remove that anoying check engine light that wont let me pass an inspection? If anyone has use one that works, please hook me up, so i can get one thats is known for working. Thanx alot

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Brugalontherocks &raquo;</TD></TR><TR><TD CLASS="quote">Hey Relic1, i got all those things from Radio Shack.... BUT, i had a problem getting the R1, R2, R3, R4 because i dont know the voltage i need, i needed to know if it was 1/4w or 1/2w or 1w, i wish the part number was on the link you showed, very good help though, thanx and another thing, is all this ok to do on my obd2 civic? cause i notice the page is for toyota</TD></TR></TABLE>
there is very little power involved with this setup so the 1/4 watt versions will be more than enough.

one 1kohm 1watt resistor (R.S. part #271-153) will get rid of the P0141. like I mentioned before.

the 'MIL eliminitor' is a bad term to use. there are three different versions that I've seen. one a set of tantalum capacitors that supposedly decrease the transition time and voltage sent from the secondary O2 so the ECU thinks that the cat is there. I've never seen this work for very long.
second is basically an O2 simulator but it does not bypass the heater.
Third is an O2 fouler that can be picked up for cheap from any parts store.

the second two setups seem to work fairly well, with little rejection from the ECU. IF the cars O2 system is like honda's setup then the O2 simulator is the way to go, nothing to go bad so it will last virtually forever. Some manufacturers use a different form of O2 siganl (it has a voltage offset built into the signal) and the O2 simulator will not work with it. So the fouler trick is the only way to go, but you're still at the mercy of the O2 going bad on you.

 

maybe something you could possibly look into
im using this setup with a test pipe. 500 miles so far on my 99 si and no CEL
http://forums.evolutionm.net/showthread.php?t=114931

 

i ordered one on ebay.... but wont wait for the long delivery, plan on going to pep boys for that fouler, btw, Can i pass inspection with this if my cel goes off? and for Relic 1, incase this fouler doesnt work, and i make my own thing here, would 1/2 w resistors burn me? cause thats all they had in this Radio shack

 

http://forums.evolutionm.net/showthread.php?t=114931
that's the fouler trick and it does work on all types of O2 sensors.

you can always use higher wattage resistors, larger wattage usually mean larger parts though.
I've built this circuit in surface mount parts a few times, so any wattage more than 1/32 is fine.

 

SHIIIIIZIT.... the 02 sim (fouler) didnt work, probably gonna try that "make my self fix" (relic1), btw u wouldnt have a pic of how it lookds done? one question, i removed the heat sink or sheild from the car (that rusty crap that covers the headers and cat, is there any risk in doing that? thanx in advanced... (car is 96 d16y7 for now)

 

Bring this back...

I am trying to find a place online where I can buy an o2 simulator and its not working out for me. I am throwing code 65, oxygen sensor heater. I do not have a bung for a secondary sensor and the de-fouler trick. Will the simple 1kohm resistor between the heater wires work, or will i still get a cel for the lack of signal?

Thanks!!

 

spark plug fouler will be the best option for that

 

as i stated i don't have a secondary o2 bung so i can not use the de fouler trick!

 

youd be cheaper off having a the secondary bung welded in. less headaches...

 

thats last resort right now, i just found an o2 sim online, if that doesn't work ill have to do that. thanks

 

I just got the code P0131. On a 1999 Honda Civic.
I know it has to do with the O2 sdensor. I'm not sure where this sensor is located. I know there are 2 of em.
Manual says closest to the cylinder head b4 the cat converter.
Where exactly is this located?
i reset the ecu, drive it like maybe 4 to 5 miles then the cel comes up, and the transmission act funny. therpm revs up the car won't move then it just kicks in and takes off, is that something like the limp mode?
Any tricks or anything I can do about this?
By the way this cil came on 1 day after I changed the oil. I had a hard time with the oil filter, etc. there is something going into the engine block right above the oil filter, is that maybe a o2 sensor?

 

No this is a civic LX, it has 2 o2's. 4 wires each.
Got a code P0131. Input voltage from o2 sensor 1 in bank 1 is too low for current conditions. Retards cant put in in plain terms haha, anwyay....It says closest to the cylinder head b3 the cat converter. Not sure which of the 2 is this loc talking bout.

 

just buy one of these...


https://honda-tech.com/zerothread/1961972

/ thread

 

Yea I was reading about these defoulers, kinda like the simulators..My old 88 civic uses a 1 wire o2......just one though..


Modified by Bruce Lee at 10:02 PM 5/15/2007