Quote:

---

Quote:

---

Splicing wiring on an o2 sensor is not a good idea.You can get at the sensor if you drop the trans crossmember and lower the trans.I know it is a lot of work but can be done.

---

when you splice O2 sensors you alter the resistance of the sensor basically making it's readings worthless to the ecm. now your car probably won't run properly.

---

Are we aware that many O2s are universal, thereby requiring that the original plug be spliced on? Here at our shop, we have installed a ton of O2s, mostly used ones. And most of them had to have the plug spliced on.

We have NEVER had a problem with a splice making the reading worthless. Heck, there is a lot of variation in the output of identical O2 sensors. Have you ever tested any?

Anyway, experience with splicing plugs on and with testing both new and used O2s tells me that there is little to no chance that a good splice will have as much impact on what the controller ends up seeing as there is variation in O2s.

If in doubt, just test a few O2s. New or used.



One last point, as long as it is not kicking the CEL on, changing the down stream O2 is a waste of money. It's only job is to send a different reading to the controller, to prove that the catalytic converter is doing something.

The downstream controls nothing. It just monitors that the 'cat is making a change in the exhaust that results in a reading in down stream that is different than the up stream.

Which is why you can put a small resistor in the down stream O2 output wire to "fool" the controller when eliminating the 'cat. The engine will run no different with an inaccurate down stream O2 reading than with an accurate one. It just won't set the CEL if the down stream reading is within operating specs and different than the up stream.