Oxygen / 02 Sensor doesn't register? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

jharper · 07-30-2008, 01:12 PM

My car has been sluggish lately with slight bogging/hesitation problems. I've checked compression, spark, and fuel with no problems there. Today I disconnected my O2 sensor to see if it runs any different in open loop and absolutely nothing changed. My check engine light didn't even go on. So now what?

SoguRacing · 07-30-2008, 01:15 PM

a bad o2 sensor will not cause drivability problems. check for vacuum leaks. you chould have a bad tps. there are so many factors. we need more detailed information.

Bigsyke · 07-30-2008, 01:31 PM

Quote:

Originally Posted by SoguRacing

a bad o2 sensor will not cause drivability problems. check for vacuum leaks. you chould have a bad tps. there are so many factors. we need more detailed information.

Are you sure?

miggypq21 · 07-30-2008, 01:48 PM

Actually, a bad o2 sensor will make the car run pig rich, is your car modified any? Best thing to do would be disconnect the o2 from the harness, and use a multimeter to see what the voltage is reading if any.

Bigsyke · 07-30-2008, 02:04 PM

Just buy this http://store.summitracing.com/partdetail.asp?autofilter=1&part=NGK%2D23044&N=700 +4294907666+4294907508+4294924755+115&autoview=sku (s14)

SoguRacing · 07-30-2008, 02:09 PM

haha, i have a redtop sr. obd 1 cars dont use the full capability of the o2 sensor. the o2 just helps out at cruise and idle. i dont even have an o2 sensor wire on my car and it runs fine. it will run a bit rich but nothing noticeable unless you're checking your mileage every day. for you i would check vacuum leaks and maybe your maf sensor. those are usually the culprits. and while you're at it, check the ohms of the coolant temp sensor.

jharper · 07-30-2008, 04:20 PM

My car runs the same whether I have the o2 sensor plugged in or not. Idles perfectly and cruises no problem. All my grounds are good. My maf sensor checks out perfect as well as my tps. Car doesn't have any modifications other than emissions removal and a cooler thermostat. I can check the coolant temp sensor but I doubt that's the problem. My main problem is slow acceleration which doesn't seem to be O2 sensor related; however, I'm slightly shocked that unplugging the o2 sensor has no effect on anything.

Bigsyke · 07-30-2008, 04:24 PM

Quote:

Originally Posted by jharper

My car runs the same whether I have the o2 sensor plugged in or not. Idles perfectly and cruises no problem. All my grounds are good. My maf sensor checks out perfect as well as my tps. Car doesn't have any modifications other than emissions removal and a cooler thermostat. I can check the coolant temp sensor but I doubt that's the problem. My main problem is slow acceleration which doesn't seem to be O2 sensor related; however, I'm slightly shocked that unplugging the o2 sensor has no effect on anything.

Emissions removal as in EGR and EVAP? ouch

I am a firm believer in NOT having a cooler thermostat.

Emissions removal will affect drivability

duffman1278 · 07-30-2008, 05:28 PM

You're fine without the O2 sensor disconnected. Check the vacuum lines as stated.

Bigsyke · 07-30-2008, 05:43 PM

Quote:

Originally Posted by duffman1278

You're fine without the O2 sensor disconnected. Check the vacuum lines as stated.

Can I just stop you there;

Please tell my why Nissan placed an o2 sensor anywhere in, or outside of the vehicle? If it is just meant to be removed like fresh wrapping paper on that new lego set, then I will remove .03lbs of weight off the manifold.

The OP didnt ask if he should leave the o2 off.....IMO its one of the more important sensors on the car.

this is if you meant to OP can leave his O2 sensor off....

mifesto · 07-30-2008, 05:54 PM

well cant say that statement for any o2 sensor haha... secondary o2 is garbage

Bigsyke · 07-30-2008, 05:58 PM

Quote:

Originally Posted by mifesto

well cant say that statement for any o2 sensor haha... secondary o2 is garbage

2nd is for OBDI, OBDII is for catalyst datalogging.

Primary O2, OBDI/II you need it

jharper · 07-30-2008, 07:26 PM

I bought the car without the emissions equipment installed and I've never had a problem, ever. Same goes for the thermostat.

I also agree that the o2 is one of the more important sensors in the vehicle which is why I'm confused as to why it doesn't make a difference whether it's plug in or not on my particular vehicle. If it's not registering with the computer I'd like to know why as it could effect my fuel efficiency as well as acceleration. The motor is not running at the same efficiency as it was new and it's important for the computer to have the feedback necessary to make the appropriate adjustments.

Is there a way to find if the o2 sensor is sending any kind of signal to the computer? I can buy a new one but it won't matter if the ecu isn't receiving anything. Also, shouldn't the check engine light come on when I unplug the sensor?

Bigsyke · 07-30-2008, 07:38 PM

grab the FSM and see if its a 2 trip CEL

duffman1278 · 07-30-2008, 11:58 PM

Yea I meant that he can leave his O2 sensor off, its pretty much for emissions. Yes it does help the car from running so rich, as a pose to not running an O2 sensor. I've ran my SR without an O2 sensor and when I plugged one in, I could barely tell the difference, if any. I'm just trying to isolate as many things that might not be the cause of his issue.

To the OP, keep us updated if you find the solution for future reference

pink godzila · 07-31-2008, 12:04 AM

Might be bad Injector!! or you need to clean your Intake Manifold !!Try that!!

SoguRacing · 07-31-2008, 12:05 AM

then check your maf and timing. your timing could be off

mifesto · 07-31-2008, 06:49 AM

Quote:

Originally Posted by Bigsyke

2nd is for OBDI, OBDII is for catalyst datalogging.

Primary O2, OBDI/II you need it

yes exactly... garbage ... who needs emissions! haha

jharper · 07-31-2008, 10:11 AM

I found a small tear in my intake after the maf and taped it up. That solved the stumbling/hesitation problem but the car still feels sluggish compared to another 240sx I drove a couple weeks ago.

My car seems to have the same acceleration at 3k rpms as it does at 5k. It also seems to accelerate the same whether it's at 50% throttle or 100%. I'll go through the fuel system to make sure I have plenty of fuel pressure, clean injectors and fuel filter. I questioned the o2 sensor initially because the slight backfiring between shifts indicates to me it could be running slightly rich.

I am surprised to find such a discrepancy between people regarding the o2 sensor... some posts note their cars running crazy rich blowing smoke everywhere and others not noticing a difference at all. Even if it means getting one or two more mpg on the highway, I'd prefer to know whether it's working correctly or not.

phatkatsquad · 08-05-2008, 11:00 PM

Quote:

Originally Posted by jharper

I bought the car without the emissions equipment installed and I've never had a problem, ever. Same goes for the thermostat.

I also agree that the o2 is one of the more important sensors in the vehicle which is why I'm confused as to why it doesn't make a difference whether it's plug in or not on my particular vehicle. If it's not registering with the computer I'd like to know why as it could effect my fuel efficiency as well as acceleration. The motor is not running at the same efficiency as it was new and it's important for the computer to have the feedback necessary to make the appropriate adjustments.

Is there a way to find if the o2 sensor is sending any kind of signal to the computer? I can buy a new one but it won't matter if the ecu isn't receiving anything. Also, shouldn't the check engine light come on when I unplug the sensor?

k cooler thermostat bad cause that ecu is programmed to go to close loop at a certain temperature and by you replacing it with a different one it will just stay in open loop. and we all know in open loop that ecu is controlling everything and its ignoring almost every input sensor. so yeah right now it probably just running in open loop just trying to get to operating temperature so its dumping shit load of fuel to get it hot which explains the lack of power. so yeah if the computer never goes to close loop it pretty much ignoring everything like the 02 maf map.
now to check the 02 disconnect the harness and use a volt meter to place the lead on the signal and another on a good ground.
now check voltage if its around .02 its running lean and it if it goes to .08 its running rich. if it dosent read jack it dosent have good ground from the manifold duh or the 02 is just no good or contaminted.
now to check if the computer is reciveng the signal back probe on the ecu put a lead on the signal wire at the ecu just careful not to pierece the insulation. now wat ever you read thats wat the computer is reading. just make sure to discharge your self before handling the ecu.
now for all of yall who think im a dumbass for writing this go ahead talk all your shit cause im just here to help out.

07-30-2008, 01:12 PM	#1
jharper Join Date: May 2007 Location: Michigan Posts: 4 Trader Rating: (0) Feedback Score: 0 reviews	Oxygen / 02 Sensor doesn't register? My car has been sluggish lately with slight bogging/hesitation problems. I've checked compression, spark, and fuel with no problems there. Today I disconnected my O2 sensor to see if it runs any different in open loop and absolutely nothing changed. My check engine light didn't even go on. So now what?

07-30-2008, 01:15 PM	#2
SoguRacing Post Whore! Join Date: Nov 2007 Location: (714) Age: 38 Posts: 2,967 Trader Rating: (23) Rides Gallery: SoguRacing Feedback Score: 23 reviews	a bad o2 sensor will not cause drivability problems. check for vacuum leaks. you chould have a bad tps. there are so many factors. we need more detailed information. __________________ Pre Tune Checkup! Compression,LeakDown,Vacuum Test $80. Cams Install: $180

07-30-2008, 01:48 PM	#4
miggypq21 Zilvia Junkie Join Date: Jul 2007 Location: Houston, Texas Posts: 558 Trader Rating: (3) Rides Gallery: miggypq21 Feedback Score: 3 reviews	Actually, a bad o2 sensor will make the car run pig rich, is your car modified any? Best thing to do would be disconnect the o2 from the harness, and use a multimeter to see what the voltage is reading if any. __________________ http://fatcatsquad.tumblr.com

07-30-2008, 02:09 PM	#6
SoguRacing Post Whore! Join Date: Nov 2007 Location: (714) Age: 38 Posts: 2,967 Trader Rating: (23) Rides Gallery: SoguRacing Feedback Score: 23 reviews	haha, i have a redtop sr. obd 1 cars dont use the full capability of the o2 sensor. the o2 just helps out at cruise and idle. i dont even have an o2 sensor wire on my car and it runs fine. it will run a bit rich but nothing noticeable unless you're checking your mileage every day. for you i would check vacuum leaks and maybe your maf sensor. those are usually the culprits. and while you're at it, check the ohms of the coolant temp sensor. __________________ Pre Tune Checkup! Compression,LeakDown,Vacuum Test $80. Cams Install: $180

07-31-2008, 12:05 AM	#17
SoguRacing Post Whore! Join Date: Nov 2007 Location: (714) Age: 38 Posts: 2,967 Trader Rating: (23) Rides Gallery: SoguRacing Feedback Score: 23 reviews	then check your maf and timing. your timing could be off __________________ Pre Tune Checkup! Compression,LeakDown,Vacuum Test $80. Cams Install: $180

07-30-2008, 02:04 PM	#5
Bigsyke Zilvia FREAK! Join Date: Jun 2008 Location: NA Age: 39 Posts: 1,342 Trader Rating: (0) Feedback Score: 0 reviews	Just buy this http://store.summitracing.com/partdetail.asp?autofilter=1&part=NGK%2D23044&N=700 +4294907666+4294907508+4294924755+115&autoview=sku (s14)

07-30-2008, 04:20 PM	#7
jharper Join Date: May 2007 Location: Michigan Posts: 4 Trader Rating: (0) Feedback Score: 0 reviews	My car runs the same whether I have the o2 sensor plugged in or not. Idles perfectly and cruises no problem. All my grounds are good. My maf sensor checks out perfect as well as my tps. Car doesn't have any modifications other than emissions removal and a cooler thermostat. I can check the coolant temp sensor but I doubt that's the problem. My main problem is slow acceleration which doesn't seem to be O2 sensor related; however, I'm slightly shocked that unplugging the o2 sensor has no effect on anything.

07-30-2008, 05:28 PM	#9
duffman1278 Post Whore! Join Date: Apr 2007 Location: Covina Age: 36 Posts: 2,844 Trader Rating: (8) Rides Gallery: duffman1278 Feedback Score: 8 reviews	You're fine without the O2 sensor disconnected. Check the vacuum lines as stated.

07-30-2008, 05:54 PM	#11
mifesto Zilvia Member Join Date: Jul 2007 Location: NJ Posts: 209 Trader Rating: (2) Feedback Score: 2 reviews	well cant say that statement for any o2 sensor haha... secondary o2 is garbage

07-30-2008, 07:26 PM	#13
jharper Join Date: May 2007 Location: Michigan Posts: 4 Trader Rating: (0) Feedback Score: 0 reviews	I bought the car without the emissions equipment installed and I've never had a problem, ever. Same goes for the thermostat. I also agree that the o2 is one of the more important sensors in the vehicle which is why I'm confused as to why it doesn't make a difference whether it's plug in or not on my particular vehicle. If it's not registering with the computer I'd like to know why as it could effect my fuel efficiency as well as acceleration. The motor is not running at the same efficiency as it was new and it's important for the computer to have the feedback necessary to make the appropriate adjustments. Is there a way to find if the o2 sensor is sending any kind of signal to the computer? I can buy a new one but it won't matter if the ecu isn't receiving anything. Also, shouldn't the check engine light come on when I unplug the sensor?

07-30-2008, 07:38 PM	#14
Bigsyke Zilvia FREAK! Join Date: Jun 2008 Location: NA Age: 39 Posts: 1,342 Trader Rating: (0) Feedback Score: 0 reviews	grab the FSM and see if its a 2 trip CEL

07-30-2008, 11:58 PM	#15
duffman1278 Post Whore! Join Date: Apr 2007 Location: Covina Age: 36 Posts: 2,844 Trader Rating: (8) Rides Gallery: duffman1278 Feedback Score: 8 reviews	Yea I meant that he can leave his O2 sensor off, its pretty much for emissions. Yes it does help the car from running so rich, as a pose to not running an O2 sensor. I've ran my SR without an O2 sensor and when I plugged one in, I could barely tell the difference, if any. I'm just trying to isolate as many things that might not be the cause of his issue. To the OP, keep us updated if you find the solution for future reference

07-31-2008, 12:04 AM	#16
pink godzila Post Whore! Join Date: Dec 2007 Location: SoCal / Japan Tokyo Posts: 4,179 Trader Rating: (226) Feedback Score: 226 reviews	Might be bad Injector!! or you need to clean your Intake Manifold !!Try that!!

07-31-2008, 10:11 AM	#19
jharper Join Date: May 2007 Location: Michigan Posts: 4 Trader Rating: (0) Feedback Score: 0 reviews	I found a small tear in my intake after the maf and taped it up. That solved the stumbling/hesitation problem but the car still feels sluggish compared to another 240sx I drove a couple weeks ago. My car seems to have the same acceleration at 3k rpms as it does at 5k. It also seems to accelerate the same whether it's at 50% throttle or 100%. I'll go through the fuel system to make sure I have plenty of fuel pressure, clean injectors and fuel filter. I questioned the o2 sensor initially because the slight backfiring between shifts indicates to me it could be running slightly rich. I am surprised to find such a discrepancy between people regarding the o2 sensor... some posts note their cars running crazy rich blowing smoke everywhere and others not noticing a difference at all. Even if it means getting one or two more mpg on the highway, I'd prefer to know whether it's working correctly or not. Last edited by jharper; 07-31-2008 at 01:31 PM..