S70 O2 Sensor

smithy · Post by **smithy** » 01 Jun 2005, 08:32

I need to replace my front O2 sensor in my '98 S70 turbo. I'm trying to find the cheapest option since these things are so darn expensive and I've found a new sensor for $100. It is a Walker brand sensor. My questions is this: If I put a Walker in the front and leave the original OEM sensor (Bosch?) in the rear, will it cause problems with the car? I've heard that you need to replace both sensors at the same time to keep the system at its optimum efficiency but I had my doubts. I'm just trying to be cheap but I definitely want to do it right.

Guest · Post by **Guest** » 01 Jun 2005, 09:47

I'm no expert but I thought I read in the forums here where they recommend you change these things in "pairs" otherwise you may still get false code readings (console lights staying on) . It may just be a matter of resetting the computer, however.

Does a second opinion confirm that it is, in fact, an O2 sensor required?

White850Turbo · Post by **White850Turbo** » 01 Jun 2005, 11:52

Guest wrote:I'm no expert but I thought I read in the forums here where they recommend you change these things in "pairs" otherwise you may still get false code readings (console lights staying on) . It may just be a matter of resetting the computer, however.

Does a second opinion confirm that it is, in fact, an O2 sensor required?

That is really only an issue with the later model N/A cars that use the Denso engine management systems. That being said, I would highly recommend going back with the OEM Bosch sensor as people seem to have problems with the aftermarket ones. I got a brand new OEM direct fit Bosch o2 sensor on eBay a while back for $90.

Guest · Post by **Guest** » 01 Jun 2005, 13:29

Thank you for your input. I'll keep searching for a Bosch sensor. The Walker part was found on Ebay. Hopefully I can find the Bosch soon as well.
I determined that I needed a new O2 sensor because I got a CEL and then pulled a code for the sensor. The rich mixture has definitely reared its ugly head in the form of a severe drop in mileage and loss in pickup. I checked for vacuum leaks and everything seemed fine. Hence the O2 sensor. Now I just have to ante up and buy the darn thing.

Jot · Post by **Jot** » 01 Jun 2005, 14:14

Try www.eeuroparts.com they offer free shipping from CT.

smithy · Post by **smithy** » 27 Jun 2005, 09:20

Thanks for the tip. Definetely the cheapest around. Got some other stuff while I was on there! Hello sensor, good bye CEL!