RylAssassin

Im having a problem with my o2 sensor. Im almost possitive its not working but i dont know how to check it. I looked in the FSM for a check for it and i couldent even find the damn o2 sensor.

First of all i installed a bosch universal that was listed for the vehicle. I bought it at autozone it only costs 16 bucks. I installed an a/f gauge as well and its reading nothing.

The question(s) i had was that with the o2 sensor not working how does this effect the engine? It also seems my gas milage is being affected and the idle is a little strange. Could these be causes of a none working o2 sensor??
Thanks

NZConvertible

Put a voltmeter on the ECU's O2 sensor pin (see below). Once the sensor's warmed up it should give a 0-1V signal that varies with mixture strength; 0V being very lean, 1V being very rich, and 0.4-0.6V being stoichiometric.

Did you connect the A/F gauge to the O2 sensor wire in the engine bay? If so you have probably shorted the signal wire to the surrounding shield wire, sending the signal to ground. Neither the ECU or A/F gauge will get a signal if you do that. To avoid this A/F gauges should be connected at the ECU where the wire isn't shielded.

Ther only effect a non-functional O2 sensor has is slightly higher fuel consumption and higher emissions. The car will act completely normally, including at idle.

BiG WaNkLeR

I just recently bought my first T2 and want to check mine as well. I haven't seen the gang plugs to an ecu for a while as I sold off all my blown n/a's and just getting back onto the forum.

So having the car off or running, and do I check it at the gang plug or is there a way to read it while the plug is intact to the ECU?

sorry if this is a super newbie question

WAYNE88N/A

The plug will be ON the ECU. In fact, every voltage reading you do at the ECU will be plug on, unless you're trying to isolate something for troubleshooting...Try this:

https://www.rx7club.com/showthread.p...leshooting+ECU

RylAssassin

NZ, my factory o2 sensor plug broke off so i stripped away the shielding on the wire and soldered wire to the middle wire then connected it with a spade connector to the universal o2 sensor. Will this still cause the o2 sensor to ground?

WAYNE88N/A

Don't want to jump on NZ, but he probably won't be on for a while. He would say something akin to this though, I would think:

As long as the center conductor is not touching the outer shield, and the outer shield is grounded SOMEWHERE along its run, you should be OK.

If there is not enough shield left to ground at the sensor itself, you can ground the other end (which will be at the harness plug in the engine bay), or you could strip the insulation anywhere in between to ground the shield.

Note that there are two different shielded runs for the O2 sensor- the sensor side and the ECU side (the shield does not "jump" across the plug in the engine bay), and both have to be grounded for the shields to do their job properly...

NZConvertible

What he said...