AMBiEN22

Car: 1994 Civic Hatch CX
Motor: D16z6 VTEC SOHC
Wiring harness: Stock CX wiring harness [Just finished wiring vtec]
ECU: P28

Question: I'm about to replace a primary oxygen sensor on my car and was wondering if its flipping the code with a wiring issue. I bring this up because i just wired VTEC because that was not wired with the original harness. I may just be overthinking this and the O2 sensor is faulty. Want to double check that i am not replacing a good O2 Sensor but the wiring is just incorrect as the motor was swapped.

I will be following this diagram for removal of old sensor.


Looks easy enough taking off the heat shield and unscrewing the O2 sensor... or is there more than that?

Thanks ahead of time...

AMBiEN22

bump....

grumblemarc

iTrader: (4)

Get an O2 sensor removal socket. I tried with a regular socket and no go.

AMBiEN22

Yeah sounds good having a buddy help me out anyways to save me a headache hes got lots of tools and good cheap labor.

Former User

Before you remove the sensor, test whether the plug gets voltage and also measure the resistance of the heater element.

AMBiEN22

How do i measure the plug i know its a four prong? but what prongs? also, my voltage meter only has only one skewer if you will other is a round metal element.

AMBiEN22

Bump, anyone have a wiring schematic for the whole O2 sensor circuit. Also my OBD1 D16z6 with I'm assuming the original cx harness only needs a primary O2 sensor because the one after the cat is not hooked up...

hyperblu

For one, your looking at wrong o2 sensor... There is an upstream and a downstream o2... The downstream is the "heated" o2 after the cat... If your upstream was bad you would know it... your car would run like poo and your afr's would be all over the place... However, the rear o2 is pretty much useless and is for emission reasons only...

Former User

^An OBD1 D16Z6 only has one O2 sensor (primary).

The Yel/Blk wire in the wire harness connector provides voltage for the heater element.

Here's how to measure the resistance:

AMBiEN22

Alright cool will try to test the ohms on it tomorrow at some point. But that is what i thought that there was only one O2 sensor and not two. Well i will test the O2 Sensor see if its any good pretty sure its going to be crap. I thought these things were cheap but i guess i was looking at the wrong price cause auto zone said 60 and i thought i read 16 some were =/

AMBiEN22

Well got excited and tried to test the ohms on the sensor but was getting eaten alive by mosquito's so i gave up.

- need a garage =/

AMBiEN22

Sorry to tripple post but on my O2 sensor i have now their is 2 black wires and 1 white and 1 green.

Was this
referring to the wiring that goes to the ECU?

Former User

solution = DEET spray

AMBiEN22

lol i'm just going to wait till the sun comes back up . Also thank you for the fast reply i appreciate it but what about that post after the DEET solution post lol.

Former User

The wires you mention are on the sensor side. The Yel/Blk wire is on the wire harness side.

AMBiEN22

With car off sensor side C and D should read between the above ohms?

Also is there a way i can test the cables that go to the ECU to make sure they are wired properly with my tester?

Former User

Yes

First measure voltage to body ground at the Yel/Blk wire with the key in ON(II).