I've had this performance problem for a while now, and it's driving me crazy! My car has been ridiculously slow for over a year now. At first I had a P0300 random multi-cylinder misfire code running for a long time. I got that fixed after about 6 months by replacing a coil in cylinder 2. My performance improved slightly. Then the code came back... then went away. Another code popped up that said misfire in cylinder 2. I did nothing about it, and that went away. Through this whole time my car has been slower than normal.

Recently, my car has developed some new symptoms. Now (on top of being slower) it hesitates upon heavy throttle, and is much slower then it has been upon heavy throttle through the RPM band. Also my engine has developed a loud ticking noise that gets faster as the engine speed increases. Today, I get my computer scanned and I get P1147, P0139, P0159, and P1167, which are "maximum voltage not met" and "slow circuit response" in bank 1 sensor 2, and bank 2 sensor 2.

I have headers, y-pipe, an O2 sim, and no tune. Conveniently, those are the same sensors connected to the O2 sim. I'll probably replace those sensors. However, I have a sneaking suspiscion that it's not just the O2 sensors, and there may be another underlying problem that's causing the O2 sensors to fail since I've had this performance problem that I couldn't figure out. Has anybody had any experience with this type of issue, or have a guess at what it may be?

 

running rich will cause things to foul up

 

i've been running rich for a long time.. so you think my solution is to get tuned?

 

If you're running a simulator, are the secondary sensors just there to fool the heater circuit?

If so, you can eliminate the secondary sensors completely like I did, by wiring (2) 10ohm, 10watt ceramic resistors in series for each sensor.

Also, the secondary sensors should have no effect on the way the car runs, as they're there only to monitor catalyst efficiency. I have read however, that if there is a malfunction in both of the primary o2's, the ECU will resort to the secondary o2's for its AFR readings.

Have you ever had any codes for the primary o2's?

I have the dual output simulator from o2sim.com, and every once in a while, after cruising at around 55mph for around 20 minutes, I'll get a p1147 and 1167.

I believe that is because the simulator doesn't output exactly the right voltage to the ECU, so the ECU throws the code. It never effects my drivability though, so I just clear the code.

If you want, we can meet up sometime this week and wire up those heater resistors. (I'm Jake if you didn't know)

 

oh, yeah i didn't know this was you jake.. no, i've never had any codes for the primary O2's.. or any O2 codes besides when i put headears on and i was running them without the sim for a while.. yeah, right now the sensors are zip-tied beside the engine

2 questions about the ceramic resistors:

1. i'm assuming they do the same job as the O2 sim, which is to fool the ECU, making it think that there are working O2 sensors and cats.. right?

2. if you eliminate the secondary O2s all together, the resistors would wire right into the O2 sockets?

 

There are two parts of the secondary o2's that need to be simulated.

There's the heater system and the actual oxygen monitor.

The resistors are there to fool the ECU into thinking that the heater circuit is there.

These resistors are used in conjunction with the o2 simulator, allowing the secondary o2's to be complete removed, so they wont have to hang in your engine bay.

Maybe you can get your car to the dyno and have them give you a printout of your AFR's at WOT and see if they're out of wack. Let me know if you want help with the resistors.

 

yeah, i might take you up on that.. where did you get your resistors and how much did they run you?

 

I got them at Radio-shack and they were no more than $6.

 

I need to do that wiring jake, think you could pm me how u did yours? I've got the dual sim installed however one of my secondary o2's is cutt so I need to do this. I've been waiting for a wrecked max near me to grab the o2 off of but it's been over 2 months and nothing so far with inspection on it's way.
Lmk. thanks

 

i had the same codes in my 01 and i have headers and an o2 sim also and my problem was the o2 simulator i had in for like 2-3 years already stopped working, wired in a new o2 sim and problem solved

 

Glad I found this thread!! I am having almost the exact same problem. My codes are a little different, but I am getting hesitation (Even with the new 2k1 MAF swap - it ran great for a month and than this started to happen) and the car feels slower. Sometimes it hesitates, sometimes it doesn't.

http://forums.maxima.org/5th-generat...elerating.html

from that thread...
Got the breather filter on tonight and it feels like it is running better, but I still feel some hesitation - sometimes. Will an o2 SIM fix my codes? Should I replace the o2s first and than run the SIM? What happens if you get a SES for a primary o2? What can be done about that?

Since I have OBX headers, I have bungs for all the o2s. Would just going the old anti-fouler route help me get rid of any of these codes? I really just want the car to run right and I need some direction. Thanks in advance for all the help!

 

ok, well i'm getting an SAFC 2 black to get tuned.. hopefully this will fix at least SOME of my performance problems

 

Update update update??? My 2002 SE Auto decided to start doing the hesitation on acceleration but only in 2nd gear and only past 3,000 RPM. I definitely hear loud sputtering/ticking sound at 4,000 RPM. Been talking with someone on the ORG and was told this sounds like a plugged catalytic converter.

So I searched some but did not find much information on testing to confirm the three way catalyst is jacked up or plugged.

Plus I did a little reading here http://www.aa1car.com/library/converter.htm

Edit: Might help if I mention the only codes I get right now are 1147 and 0139. I dropped in a new oxygen sensor for one of the codes, cant recall which one, and it's still present. TSB from Nissan says to replace BOTH rear oxygen sensors, it DTC returns to reflash the ECM which bumps up the tolerence for this DTC.