Need advice on Check Engine Light

N

NRG

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I turned on my engine (2000 model) this morning and I noticed the check engline light. After reading some previous thread on this forum about CEL, I took the "clock" fuse out for 10 minutes to erase the check engine light to check if it was a false alarm.

I decided to drive the car around the block. The car runs fine until I came to a stop light. All of a sudden, the car turned off with the oil light on. The car wouldn't operate, so I turned on the ignition key and started the car again. Strange. I drove the car back home immediately. The oil was adequate.

1) Why did the car shutdown while I was parked at the stop light?
2) I read about the code retreiving method, but I don't feel comfortable. Should I bring it to Autozone to read the code? If so, how much do they charge for that service?
3) I did install a new exhaust about 500 miles ago.

Can you provide advice in what I should do? Should I re-install the stock exhaust? Possible bad oxygen sensor?

Any advice is appreciated.
 
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Until you get the code which may be gone since you pulled the clock fuse everything is just a guess. Having the engine die may be related to the reset of the computer and it having to re-learn the fuel trims. I believe AutoZone does the code scan for free.
 
Thanks BrianK for the response.

The CEL came on this morning. I drove the car to Autozone and they let me borrowed their OBD2 reader.

P0141

Rear Secondary HO2S Heater Circuit Malfunction (Bank 1 Sensor 2)

1) Is this a serious problem?
2) Do I need to fix it immediately?
3) Should I be driving the car around or should it be limited driving until the problem is fixed?
4) Can I fix this myself or do I need a mechanic with special tools, etc?

thanks in advance,
 
a thought on why your car shutdown...maybe you did not push the fusible link back in all the way and you had a momentary loss of power to your on board computer. I would check the fusible link as it is a tight fit.

What was the scope of work for the exhaust replacement (i.e. did it include replacement of the two catalytic converters and two O2 sensors)?

Defective O2 sensors are bad for the environment as they are part of your emission reduction system and your car will pollute more with bad O2 sensors. You will, however, notice little impact on the drivability of your car and there will be no damage to the engine. Actually, they reason we have check engine warning lights is because the average person would not know if there was a problem with the car's emission system.
 
The exhaust replacement was just of "TAITEC JGTC Parallel Exit Exhaust" from Science Of Speed. Do I have to change the sensors when I replace the exhaust?

Can I replace the sensor myself without difficulty? I can do my own oil change only to the car.

dalybo said:
a thought on why your car shutdown...maybe you did not push the fusible link back in all the way and you had a momentary loss of power to your on board computer. I would check the fusible link as it is a tight fit.

What was the scope of work for the exhaust replacement (i.e. did it include replacement of the two catalytic converters and two O2 sensors)?

Defective O2 sensors are bad for the environment as they are part of your emission reduction system and your car will pollute more with bad O2 sensors. You will, however, notice little impact on the drivability of your car and there will be no damage to the engine. Actually, they reason we have check engine warning lights is because the average person would not know if there was a problem with the car's emission system.
Click to expand...
 
The two oxygen sensors are located in the section of the exhaust system BEFORE each of the two catalytic converters. It sounds like the portion of the exhaust system that was replaced was the section AFTER the catalytic converters. If so, the oxygen sensors were not involved in the portion of exhaust system that was replaced by the exit exhaust pipes.

Replacing the oxygen sensors involves 1) unplugging the electrical connectors (which is a bit tricky as they have locking mechanism that need to be carefully opened by using a screw driver to depress a clip to release the male and female connector sections) and 2) unscrewing the sensors with an open end wrench. Installing new sensors is more simple then the removal as the electrical connectors just clip together easily (with no screw driver) as they are meant to be connected rather then not. Before screwing in the sensor apply a small amount of never seize grease to the sensor threads (this stuff is supplied with the new sensors). Sensors are expensive...about $250 each.
 
Thanks guys! Is it better to replace 2 sensors at the same time? I remember that it was recommended to replace 2 oxygen sensor on my bmw at the same time even though one was reported as a problem.
 
You have 4 sensors in your OBDII car; the primary sensors control your mixture; the secondary ones are to check the efficiency of your cat & do not trim the fuel/air ratio to compensate for anything - just alarm.
Therefor there is no immediate concern to not drive the car, or particular hurry to get to it.
As far as the momentary stall, I agree with Brian that the ECM was probably still learning to trim after the fuse pull which would clear the registers of the previous trim information.

I believe your emissions warranty should still be applicable for a 2000 model car but not sure if the O2 sensors are considerd "major" components - ask your dealer to confirm.

edit: As I research further, it appears the O2 sensors themsleves are not warranted beyond the primary car warranty coverage.
 
Thanks everyone for their inputs. Since the car has been in the garage for the winter, I have decided to change it myself in the next couple of weeks.

FYI...

The part # for this particular O2 sensor replacement for 1995-05 is

36542-PR7-A51.

Thanks to member favetita.

Make sure to confirm that this part # is made for your car before purchasing.
 
That number comes back as the O2 sensor for a 3.2 car, bank 2 sensor 2.
Let me know if it is correct. I think it should be 36541-PR7-A01.

CORRECTION: The number should be 36542-PR7-A01
 
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D'Ecosse said:
You have 4 sensors in your OBDII car; the primary sensors control your mixture; the secondary ones are to check the efficiency of your cat & do not trim the fuel/air ratio to compensate for anything - just alarm.
Therefor there is no immediate concern to not drive the car, or particular hurry to get to it.
Click to expand...
I'm no expert but I dont know how true this is. If the secondary is bad it may cause the ECU to try to fix the problem. Which if the readings are bad any fix it tries will be bad. Having a bad Primary O2 can cause the car to run extremely lean. Which is bad, But I dont know how much control if any the secondary has but it is something I would definitely check into or ask an expert about.
 
vtec888 said:
...Since the car has been in the garage for the winter,...QUOTE]

since when does Milpitas have winter? :mad: I used to work in Milpitas and I don't ever recall getting weather much below 45 degrees. Though it has been 15 years, I doubt if an ice age has taken hold... :tongue:
Click to expand...
 
I consider "raining season" as winter :) The car does not see rain :)

nsx2tall said:
vtec888 said:
...Since the car has been in the garage for the winter,...QUOTE]

since when does Milpitas have winter? :mad: I used to work in Milpitas and I don't ever recall getting weather much below 45 degrees. Though it has been 15 years, I doubt if an ice age has taken hold... :tongue:
Click to expand...
Click to expand...
 
Hello,

Based on the picture below, can someone tell me which one is considered as "bank 1 and sensor 2"?

The picture was taken from the rear view.

Many thanks in advance,

img2671a6ue.jpg


Update 01/11/06: "The bank 1 sensor 2" is the one on top in the picture. I have learned that bank 1 mean it's the one attached to the cylinder 1 (which is the located in the rear next to the tail). Both of the sensors in the picture have different end connector shape. Luckily, I ordered the correct sensors.

The installation was very simple. Lift up the car after a 5 minutes engine warm-up. You'll need an adjustable wrench for the job (the bigger the better - makes it easy to loosen the sensor). The O2 sensor socket WILL NOT fit for this particular sensor because the inteference with the exhaust pipe. You'll need an adjustable wrench. I tried using the universal O2 sensor socket, but the socket wouldn't fit around the sensor. Unplugging the sensor was simple...just use your hand to press down the end connector and detach it. When everything is in place, just reset the CEL by unplugging the clock fuse. After 40 miles of driving, the CEL is history now.
 
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Code p0141 is for the Oxygen sensor heater, not the sensor itself..the heater is inside the sensor assy..the heater helps to bring the sensor up to temp faster than without, and bring the car into "closed loop" operation faster...when the engine is cold the ECU does not use the O2 sensors for adjusting mixture...only after the proper temp is reached the system goes into "closed loop" and monitors O2 sensor output...your O2 sensor is still functioning when the car is warm and "Protecting our environment"..however until you replace the O2 sensor with the failed heater you will set the CEL on.
 
Hello sorry I cant help you. I was hoping I could get some help were is 02 bank 2 sensor 1 located in the exhaust. Please help thank you in advance
 
This sensor is the front bank (4,5,6) located after the cat.

HTH,
LarryB

darcy said:
Hello sorry I cant help you. I was hoping I could get some help were is 02 bank 2 sensor 1 located in the exhaust. Please help thank you in advance
Click to expand...
 
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Hi guys,

Back to the earlier part of the thread - I have the same error code for the Rear Secondary HO2S Heater Circuit Malfunction (Bank 1 Sensor 2) code (for 97 NSX). There are a couple of different part numbers listed earlier in this thread, and on calling the dealer, I get another part #. I've looked on various online parts catalogs, but can't determine which is the right one :-(

Could someone help out with the definitive answer to which is the correct part # for this O2 sensor I need please?

Cheers
 
You are very welcome my friend. With the rear secondary i would check the wiring for damage first because of the proximity of the sensor to the muffler. Especially if the exhaust or rear stabilizer bar has been replaced.

There are some other things you can try like resetting the ECU and checking the Ohm of the heater circuit in the sensor.

Good luck
Mike
 
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