Oxygen sensor broken?

Tiny
MARIOC68
  • MEMBER
  • 1995 TOYOTA COROLLA
  • 160,000 MILES
Hi,
the oxygen sensor a single cable connected to the multimeter: idle operates as follows:

https://youtu.be/lrXkZC87YJA

and accelerating a bit, up to 2500 rpm

https://youtu.be/EfIu6SXy3H0

Is normal?
Sunday, March 6th, 2016 AT 10:16 AM

39 Replies

Tiny
HMAC300
  • MECHANIC
  • 48,601 POSTS
Scan for codes if none found check fuel pressure with a gauge auto parts rent it.
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Sunday, March 6th, 2016 AT 10:48 AM
Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,004 POSTS
ARE YOU HOOKED ONLY TO THE O2 SENSOR WIRE W/ MR. VOLTMETER?

OR

ARE YOU "TAPPED INTO" THE "STILL PLUGGED IN" O2 SENSOR?

WHAT GAVE YOU THIS "BROKEN ASSUMPTION"?

THE MEDIC
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Sunday, March 6th, 2016 AT 11:15 AM
Tiny
MARIOC68
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  • 120 POSTS
Sorry, I meant if the sensor is or not damaged, not broken (wire).

Anyway, to make reading a pin was placed tip and insert the sensor cable, hence the positive signal multimeter (red wire) and mass of the battery was taken.
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Sunday, March 6th, 2016 AT 12:10 PM
Tiny
MARIOC68
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  • 120 POSTS
I did check the fuel pressure. Vacuum hose connected to the pressure regulator have 37 psi. And with the hose disconnected, 47 psi.
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Monday, March 7th, 2016 AT 11:11 AM
Tiny
HMAC300
  • MECHANIC
  • 48,601 POSTS
Ok pressure is good then what is the code you are having. It may be just eh heater circuit for O2 and will need to be replaced also check for a fuse
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Monday, March 7th, 2016 AT 12:13 PM
Tiny
MARIOC68
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  • 120 POSTS
The oxygen sensor is a single cable, no heater. It does not show me any code
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Monday, March 7th, 2016 AT 12:27 PM
Tiny
HMAC300
  • MECHANIC
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Then replace the O2 sensor I have no further comments.
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Monday, March 7th, 2016 AT 12:33 PM
Tiny
MARIOC68
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I performed the following test, assuming that I have low readings from the sensor. I sprayed wd40 in the mouth of the acceleration body, simulating rich mixing, then the readings immediately rose to over 900mV. This results in thinking of damaged sensor yet? Or what should I try?
The car did not lose power, can the sensor be the cause?
The scanner does not give me errors is OBD1
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Sunday, April 14th, 2019 AT 6:33 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Good morning

Lets back up to the beginning.

Why are you measuring the voltage at the sensor? What issue do you have that makes you think there is a problem?

Roy
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Monday, April 15th, 2019 AT 4:30 AM
Tiny
MARIOC68
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Leak power.
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Monday, April 15th, 2019 AT 4:45 AM
Tiny
ASEMASTER6371
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Got it.

The sensor will not cause a low power issue. It monitors fuel in the exhaust for fuel mapping.

https://www.2carpros.com/articles/engine-has-low-power-output

Roy
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Monday, April 15th, 2019 AT 4:49 AM
Tiny
MARIOC68
  • MEMBER
  • 120 POSTS
Hi. I disconnected the IAC valve, then I saw that the oxygen sensor readings started to work (random readings), I no longer had a static reading of 75 or 76 mV.
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Tuesday, May 14th, 2019 AT 1:56 PM
Tiny
ASEMASTER6371
  • MECHANIC
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If you have a lack of power, I would check both the fuel pressure and the cat converter for being clogged.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

https://www.2carpros.com/articles/how-to-test-an-ignition-system

Roy
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Tuesday, May 14th, 2019 AT 2:00 PM
Tiny
MARIOC68
  • MEMBER
  • 120 POSTS
How to check catalytic converter is clog?
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Tuesday, May 14th, 2019 AT 4:20 PM
Tiny
ASEMASTER6371
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You need a back pressure gauge. You remove the O2 sensor and install the gauge. Run the engine and see how much pressure. Anything greater than 1.5 lbs is a clogged converter.

Roy
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Tuesday, May 14th, 2019 AT 4:43 PM
Tiny
MARIOC68
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  • 120 POSTS
Engine idling or accelerating (up to how many rpm)?
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Tuesday, May 14th, 2019 AT 5:08 PM
Tiny
ASEMASTER6371
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Idling at 1500 rpm.

Roy
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Tuesday, May 14th, 2019 AT 5:16 PM
Tiny
MARIOC68
  • MEMBER
  • 120 POSTS
The problem with the low voltage reading of the oxygen sensor, could it be due to leakage problems in the intake or exhaust valves? Perform the test by putting a piece of paper in the exhaust, it sucks on the paper. Could you do a compression leak test?
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Tuesday, May 12th, 2020 AT 10:59 AM
Tiny
ASEMASTER6371
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Yes, if you have vacuum, then you may have a compression issue.

Pull all the plugs and do a compression test.

https://www.2carpros.com/articles/how-to-test-engine-compression

Roy
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Tuesday, May 12th, 2020 AT 11:11 AM
Tiny
MARIOC68
  • MEMBER
  • 120 POSTS
Engine compression test results:
Cylinder 1: 210 psi
Cylinder 2: 200 psi
Cylinder 3: 205 psi
Cylinder 4: 200 psi.
Note: The test was carried out 5 minutes after the engine had warmed up, with the throttle fully open, and 5 seconds when the ignition key was activated.
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Friday, May 15th, 2020 AT 2:36 PM

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