We have a '97 T-5 sedan. So the check engine light comes on. I check and the trouble code comes up slow o2 sensor, bank 1 sensor 1. So I replaced the upstream o2 sensor and cleared the codes. Life is good. Until check engine light comes on ~ a week later. Same error. Talked to the local Volvo repair guy. He says replace the downstream sensor, sometimes that's actually the trouble. Cool, done. 10 days later you guessed it, check engine light, slow o2 sensor Bank 1 Sensor 1. Ideas?

 

Use OEM O2 sensors? Makes a difference on these cars; they're finicky.

 

Bought at local parts store, don't remember whether they were Volvo. Was expensive (~$140 ea) and a direct fit. I will check today on the brand.

 

Yea, they are so finicky that I actually get OEM sensors from jy cars if they look newish. The ones from the dealer are expensive.

 

They were OE sensors that I bought. Any other experiences?

 

That's great advice. Who is the OEM manufacturer ??

I know there is Denso and Bosch and Bosch is the Manufacturer most auto parts stores sell. You can order a Denso but it will usually take a couple days to get it in at Oreilly and autozone, not sure about NAPA, advance .... .

Both IPD and FCP handle Bosch and IPD handles Denso. FCP shows a "Walker" brand but I'm pretty sure that's re-branded from someone.
FCP says that Bosch is the OEM.

Gdog, it's not personal you just happened to say it today. There are plenty others where I'm biting my lip

The trick is when you go to the dealer are you getting a "Dealer" part or are you getting a part from the Dealer?? I've worked auto parts and had dealers call us for all kinds of stuff. Your guess is as good as mine if the customer knew if the part they bought over the counter or installed was identified as coming from the auto parts store.
Sorry, I just get ruffled when people say "OEM" because usually they have no idea who the OEM really was when they say it. That and the aftermarket industry at times will build a better part in materials or sometimes design than the original part. They're lucky in that respect because they can see a failure rate that's too high and benefit from a redesign so their return rate is profitable. That's why buying a new CV shaft or Water pump is usually a better idea than going with a rebuilt. Those parts and others will actually be as good or better than the Dealer's OEM. There is also a lot of junk out there so it's not a blanket statement.

 

Hey Kfrog. Yeah it can be an ambiguous topic for sure. I get what you're saying that for some parts, aftermarket can actually be better than OE; xemodex ETMs for example. But for the sake this discussion let's limit the topic to O2 sensors, OK?

Here's my take:

1. OE = original equipment meaning (typically) what you get from the dealer but other reputable outlets sell OE as well; e.g. only O2 sensors I saw for volvo at IPD were OE. What you get at FCP depends on what they have that week; if you specify (call them up) they could likely get OE for you.
2. OEM = original equipment manufacturer who in this case would be Bosch. Often (most of the time) this is same as OE but may not have the volvo logo and packaging. But (some of the time) these may be factory 2nds meaning they (for whatever reason, could be cosmetic) didn't pass factory (e.g. volvo) standards so were rejected; part may be perfectly fine but with that caveat. Please note though; just because you buy a Bosch O2 sensor doesn't necessarily mean it was designed for your car (yeah, it's confusing). If it's right/correct it will typically have the same OE part number.
3. OE Type or OE Fitment or OE Equivalent: This is where you need to be wary. These are fancy names for aftermarket parts so any claims need to be taken with a grain of salt. I've seen lots of guys buy O2 sensors at AutoZone (or whatever local parts store is available..) and the counter guy claims the part he's selling is OEM but if you look carefully it really says something else that's not exactly "OE" or "OEM". The part may fit just fine; doesn't mean it works the same. These are the O2 sensors that people get on the forums and complain about. Again, when it comes to O2 sensors, these cars are finicky.

 

Interesting distinction. The ones I bought were Bosch.