2004.5 Kia Spectra o2 sensor question (Page 1/1)
trivet JUL 10, 08:48 AM
I have a 2004.5 Kia Spectra EX (2.0L 4 cycl) that needs a new o2 sensor. It actually has 2 o2 sensors, one right in front on the exhaust manifold and another downstream after the cat.

I ordered both, (or so I thought) and I ended up with 2 of the "downstream" sensors. Other than the connecters, are there any differences in the sensors themselves?

Can I just splice the old connector on to the new sensor, or am I better off just shipping it back and ordering a new one. I would have bought local, but the prices around her are $150+ vs. $50-$75 from Rock Auto and such.

Thanks in advance, and thanks Cliff for making this forum even better (didn't think that was possible, but happy to be wrong!)

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Tim
'87 GT Auto
Med Red Metallic
78K miles
Bay City, MI

RWDPLZ JUL 10, 10:58 AM
Many times the upstream ones are electronically different than the downstream ones. A lot of the time the downstream ones are just there to make sure the cat is working, while the upstreams feed the valuable information on air/fuel mixture in the exhaust to the computer. Best to return the one while you can and get the right one, or you might risk damaging it and not being able to return it.
E.Furgal JUL 17, 04:20 PM
I'd return both and just get the upstream one(before converter)
TONY_C JUL 19, 03:12 PM
What code did you get from the PCM? That will help determine what O2 Sensor you need. All OBD II cars have a sensor before and after the cat. The sensor ahead of the cat delivers O2 info to the PCM so it can determine the correct air/fuel ratio, the sensor after the cat measures the O2 level and compares it with the forward sensor. If the levels are too close the PCM will throw a P0420 code which means that the cat is below the efficiency threshold, and not working properly.

Edited to add, from my personal experiences with O2 sensors, I always try to get the Denso brand sensors. I have had too many cars comeback when using Bosch sensors. Just my experience but I know other mechanics who feel the same about the Denso brand. And I wouldn't cut the wires, the pinouts may be different or there may be differences between front and rear sensors. Get the correct ones.

[This message has been edited by TONY_C (edited 07-19-2012).]

trivet JUL 19, 03:31 PM
I can't remember the exact code, but it was showing a faulty O2 sensor. I ordered what I THOUGHT was a front and a rear sensor, and I got 2 rears.

I sent it back and got a front, installed both (probably only needed the front, but since I already had 2 of the rears.....) no more issues. CEL is reset, no more hesitation or codes. Rear one was cheap anyway, and easy to replace.

Thanks again for all the help!

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Tim
'87 GT Auto
Med Red Metallic
78K miles
Bay City, MI