Time for new o2?

[echase76]

Quick background: I have been throwing a CEL on a new to me V70. It takes a while to set a code, but when it does I get a P0133 Bank 1 Sensor 1. Basically, slow response from the front o2. The CEl almost always comes on when I'm cruising at low rpm with no load.

Took it in and had it smoked to check for vacuum leak. No leak. (BTW my local Midas does a smoke test for $20. Seems like a heck of a deal to me.)

Is there any hope that cleaning connections will help? Should I check the resistance of the wires that heat the sensor?

I'm starting to suspect that it is time to just suck it up and buy a new o2.

Thoughts?

[binglax09]

Replace it, once a code is set like how you stated then it's safe to assume it's actually the sensor and not an air leak. If it was an air leak you would get bank 1 rich mixture instead of slow response.

[echase76]

Thanks for the advice. It has set the code twice now, but has taken its sweet time to do so. Both times it was hundreds of miles and over a week. The CEL even turned itself off once!

[bronxnativ]

Agreed; suck it up and buy a new one. Make sure its a Bosch (Amazon has them for about $90). I dealt with that code for over a year until I finally set aside a hundred bucks to get it resolved. Hasn't come back since the replacement!

[JRL]

I have two perfectly good 1999 original Volvo 02 sensors with about 80K on them (long story, replaced when we thought they were causing an issue, they were not).
Not sure if 99 sensors work in a 98 but if they do I'll sell both of them to you pretty cheap.

Also you should consider replacing the small rear 02 HARNESS, they do go bad, (they burn up).
Very simple plug in and not expensive to buy.
If you may be interested, email me: jrl1194(at)aol.com meanwhile I will find out if they will work on a 98

[JRL]

They won't work, sorry, ignore what I said.
98 is the same as 96-97s, 99-2000s are different

[tjts1]

Replace it, its dirt cheap. I used a Bosch 13877 sensor. $15 on Amazon. Just have to crimp the 4 wires. Works great.

[echase76]

Thanks everyone for the help. JRL too bad that '99s are different of I would have bought them from you.

Plan to order one this weekend. I have a discount coupon with FCP, so pick up an OEM and a couple other things I need. That way I'll get the discount and free shipping!

[erikv11]

Replace it, its dirt cheap. I used a Bosch 13877 sensor. $15 on Amazon. Just have to crimp the 4 wires. Works great.

Just for the record, on the forum sites there is wide disagreement about putting a crimp-to-fit oxygen sensor into a Volvo. Some people say the crimp method works fine, some say it might work at first but in any case will never last more than a year before throwing a CEL. YMMV.

There is no argument about the O2 sensors with the proper connector already in place (Bosch 15097 in this case), they always work. But they cost a lot more, too.

[JRL]

Use Blue box Volvo or BOSCH (Same thing)
I forget if 98s use Densos, I think the non turbos use Densos