I searched the forum for a definitive source for O2 Simulators and came up with nothing so here's a new thread. Since installing Cattman headers and y-pipe eliminates the pre-cats, the lack of places to put the secondary O2 sensors causes the SES light to remain lit. I need to know if anyone out there has had success with an O2 Simulator and who manufactured it.

 

if you the main cat in place then you can relocate them behind the main cat essentially beside one another. you can always use a simulator like the one i got from 02simulator.com i relocated mine behind the main cat but putting a test pipe in soon.

 

extending the wires doesn't work well. Most people get a CEL from it. I have had my 02 sim for almost a year now- even passed emissions with it They only test for any codes in the ECU in my state. Works like a charm.

 

Did you use the O2 sim from O2Simulator.com?

 

I have 1 but have not put it on yet. Been running a SES light for 70K miles!!!
I'm interested to see if this works

 

Running with a SES light won't pass emissions testing in AZ

 

it won't in MD either

 

Ahhm, I started to promote www.o2simulator.com here a while ago, pioneered the P0420 and P0430 fix a while ago. I have plenty of happy .org members who have gone through installing the simulator the way I posted a "How-to" with no one saying that their car still has a CEL. In IL the car has to have NO CEL, and all the readiness tests (self tests the ECU does on its equippment) have to be set. If you simply clear your codes before going to get tested- even with no CEL they will FAIL you. Readiness Tests get cleared when the ECU is reset, and they take a long time to set- ESPECIALLY the CATALYST test. If the car has no Cats the ECU will throw a code (DTC- diagnostic trouble code) and CEL will go on. Simulator goes through and FOOLS the computer into thinking the cats are there, it passes all of its Readiness Tests and everything is kosher. They hook up their scanner to the car, read off the tests and DTCs, if everything is fine your good for 3 years. My Maxima is a gross polluter, it doesn't have a single cat ( 3 on my ride) and I sport www.o2simulator.com dual version - passes emission test in 5 min

 

I have no cats no sims an no codes. My secondary O2 sensors are parked behind what used to be a catalyst and report everything as fine.

 

I would like to get your write-up on installing the simulator. Could you post the link or email it to me. Thanks in advace.

 

For what it's worth, the O2 sim from o2simulator.com works well. It should also be noted that you must still continue to use your rear O2 sensor(s) even when the simulator is installed. The simulator will take care of the P0138, P0139, P0420, and P0430 codes, but it will not correct for the O2 heater circuit, which can cause a SES light if the O2 sensors are not installed on the vehicle.

 

I still have my main cat and associated O2 sensor. I am trying to figure out if the O2Simulator.com unit will work for the sensors that were just after the pre-cats since the Cattman headers do not have provisions. Please advise.

 

I have ordered mine and not recieved it yet -- but I think it is just simple if it is the secondary O2 sensors (which has failed for me, but the primary sensors wiring is different, someone on the forum should help in that case). The Black is the signal which is to be disconnected and o/p of simulator fed back to ECU, grey (ground), one of the white wires is +12V DC which is needed by simulator, and the other white wire is the heated wire which is used in to heat up the sensor to bring it up to normal orperating voltage ASAP during cold starts. The heated wire is also used by the ECU to get back the resistance drop so it cannot be disconnected.

The O2 simulator has a 555 timer that returns normal operating voltage 0.4- 0.7V back to ECU in intervals of 3 sec -- the ECU expects the voltage to vary in this range (which is a function of throttle response). I guess I could have build it on my own with hardware from Fry's/RadioShack but later decided to order it as I don't want to fry up my ECU.

 

I should mention that Cattman recommends installing the secondary O2 sensors in the B-pipe...my mechanic didn't fully follow the installation directions. So I guess I have this done or use a simulator...have to think about which one to do...

 

I have the Cattman setup and that is what I did. But my car has a test pipe now and that is why I need the simulator. You will need to put the O2 sensor in regardless if you use the simulator or not.

 

you can use a resistor to fool the ECU to think the heater is working. I had one on my car for a lil bit, and the 02 sensors where totally OFF the car. I already get enough questions bout the simulator itself, I don't wanna tell people how to get rid of 02s completly like I did. ECU is just looking for resistance of the heater, once that falls too low or too high it sets off a CEL for the heater circuit maulfunction. 35 bux for the Sim or 180 a PIECE of 02 sensors ?? I reather have the simulator myself.

 

Anyone with a good write-up of this install?

 

Ya mean like this one?

http://forums.maxima.org/showthread....ight=simulator

 

On the o2simulator.com website it shows the single output and dual output simulator. Which one does the maxima take? BTW I'm running the 0420 code..

 

I got the P0420 code and installed the O2 simulator and everything is fine now after 1K miles with the simulator.

 

Which one? The Single output or the Dual output? And what happened with the police?

 

Seems that most have the dual...

http://forums.maxima.org/showthread....ight=simulator

Another thread that might have some info:

http://forums.maxima.org/showthread....ight=simulator

 

More info....

00 Federal emissions vehicles just need the single output version.
00 Cali spec, 01-up need the dual version.

On a 3.0L if you have *4* wire harness plugs infront of the valve cover- you have a Cali spec vehicle. All 3.5Ls are Cali spec.

5th gens have EGR valves on the Federal Emission vehicles, 5th gens with Cali spec emissions have NO EGR valve. 02-03s have no EGR valve.

If you have no EGR valve you can run HS, Cattman, cheap Ebay headers, or dare I say... Stillen headers.

If you HAVE EGR, you Can't run HS headers without some modifications, and your better off with Cattmans.

 

I thought that:
Federal has 2 or 3 sensors plugs on the front of the engine.
Cali spec has all 4 sensors plugs on the front of the engine.

Someone correct my if I am wrong.

 

Here's how you do it...REAL easy. Forget looking under the hood, that's more work.

- Raise car
- Unplug the seal under the floor of the car to loosen the wires
- Find Rear o2 sensor wires (4- 2 white, 1 black, 2 grey)
- Splice the simulator wires (red, black, and white) to the o2 sensor wires
- Push simulator and wires back into hole and reseal with the plug
- Note the following:

simulator white taps into black wire on the o2 sensor and cut black wire (signal)
simulator black taps into grey wire (this is the ground)
simulator red taps into one of the white wires (this is the 12 volt)
leave the other white wire

SO much easier than looking under the hood.

 

ONLY works on a 4th gen and 00 Maximas, 01-up have their 02 sensor plugs under the hood.

 

I have 2 questions.
You mean that hter is only 1 grey wire on the o2 sensor?
simulator white taps into black wire on the o2 sensor and cut black wire (the wire that goes to the o2 sensor is cut & left loose?)
Thanks for the info.

 

Right. After tapping the simulator white wire into the black sensor wire, cut the side that goes to the sensor. It's feels so good to have no more "check engine" light!

 

I ordered my O2 Simulator before I checked my car to see how many O2's I had. I ordered the single output and my car has 4 O2 Sensors. Figures. I'm running the P0420 code and was wondering if I could still use this one to do the job? Also which O2 sensor is the one that is causing the problem?

 

cali spec maximas 2001
white o2 sensor harness - bank 1 sensor 2 (rear)
red o2 sensor harness - bank 2 sensor 2 (front)

you guys might as well buy the dual one just in case you ever need the second one. If you buy the single output one and somewhere down the line you need the second one you'll be stuck

 

Ok so I need to check all four O2's to find the one that has the white wire and use that one right? I'm doing this tonight and I want to get this right the first time.

 

white sleeve

 

*resurrecting an old thread*

alright here is my situation. i have a 00 fed spec 5 speed max. i have my warpspeed ypipe, about to purchase my high flow cat, magnaflow muffler and silver line tips. teh high flow cat i want/am about to purchase obviously has no o2 sensor hole, which brings me to this thread about simulators.

if i read correctly in this thread it was mentioned to keep the o2 sensor in and just tap the simulator into the wiring..btu i'm redoing my whole exhaust system. yes i have a SES light, so i guess basically..

how many o2 simulators do i need from the ypipe back?

single output?

and whatever else input you can assist me with because i am a n00b when it comes to maximas/obd2 autos

 

bump for answer to my question. do i need a single output sim or a dual output sim? whats the difference, just more wires? halp..i have t minus two weeks until i get my exhaust system done and i'm trying to cure my P0139 and P0138 codes

thanks in advance

 

It does not matter. They cost the same. I bought the dual output one just in case. but the single will do the same also. You just get the extra wire... thats all.

 

ok thanks for that information...

what's with being said since you dont have the o2 sensor in there anymore it will create a heater code?? because i am replacing the 138 and 139 codes for the sensor (sensor after the cat with the white wire)

 

I've got a O2 simulator with my headers and I have 2 downstream O2 sensor for this 03 VQ35. Shouldn't I be using a dual since there are 2 (02 sensors) or will it work with both sensor spliced together to a single output O2 simulator!

 

I'm not quite sure which O2 simulator I need. I have an 03 max, just put headers on and have a CEL. The 2 primaries are connected (the ones plugged into the headers), but the 2 others (that were in the y-pipe) are disconnected. According to this thread, I have to re-locate those O2 sensors back behind the main cat, then still purchase O2 sims to make the CEL go away? I would rather just get some 02 simulators, but they have none specific for a nissan. Which ones would I use from O2simulator.com?

 

dual output. or you can buy 2 singles. There are 2 o2's you need to simulate. I have the dual output sim and it has been flaky for over a year. Random CEL always the same code. I will be extending my secondaries to behind the main cat in the spring.

 

I have the dual output sim on my 02.No CEls.Passed Md emissions with no problem.