donbryce

Thought I'd hold off on ordering 2 of these until I get some feedback here.
Car is a 1993 ES300. I'm talking about Sensor 1, bank 1 (near firewall), and Sensor 1, bank 2 (near radiator), no rear exhaust sensor on this model. The price on these varies, like NTK about $34.00 each, delivered, and some as little as $28.00 each.

Q1. Obviously, I'm not getting the best quality...but from experience, can I expect reasonable performance/quality for the money? Denso is well over $100.00 each, Bosch around $50.00. I drive this car very little and would think cheapo new sensors would be better than old OEM ones.

Q2. I'm wondering if I can expect better fuel mileage and/or some performance benefit from new sensors? Nothing wrong with the ones in there AFAIK, but no paperwork from PO indicating they have ever been changed (current kilometers: 320,000).

yeldogt

Some report improvement when replacing them -- but we have never noticed any difference on any of our cars.

Most of the newer cars have heated sensors -- an internal heater brings the sensor up to temperature quicker than the old way of just letting the exhaust heat do it. This heating element often goes out first triggering the CEL. The whole sensor needs to be replaced to fix the CEL.

So the actual sensor part is still working in these -- most have way over 100k on them at this point. When we put in new sensors ---nothing changes --so the old sensors were working fine.

Personally I would leave them alone unless something is pointing to a problem -- then I would install an direct replacement -- don't use the generic ones or those that need the cable ends spliced on. Lots of reported problems.

donbryce

I'd expect problems with a crimped connector splice, but I can't see how a properly soldered and shrink-wrapped splice would be any different than one fitted with the OEM plug. My God, the price is like $30.00 more for the direct fit....damned expensive connector!

Now, if these are unreliable sensors, that's a different story. Thanks for the response.

snowmaker

I would use the OEM ones since they last a LOT longer.

yeldogt

An aftermarket sensor from one of the major makers that is sold as a direct fit is just that ..........the proper sensor with the correct length of wire plus any additional wire protection needed plus a new connector.

With the generic sensor - unless you know exactly what you are getting or what the engine requires -- it more of a gamble. Also, you are working with a sensitive sensor that any mistake or water intrusion into the joint will cause problems.

I understand that it looks too easy -- I'm just saying that the generic sensors cause problems with a lot of people. Also, a lot of the later Toyota sensors are idle air sensors so the generics will not work - that is why even the aftermarket sensors are almost $200.00.

For me it not worth the trouble or risk of buying something twice.

nine3es

iTrader: (3)

if you do it, post your results plzkthnx!

VicsIS350

+1

donbryce

Whew, just back from hours of reading....found this http://www.aa1car.com/library/o2sensor.htm The author is claiming that the 'newer' sensors 'breathe' through the wire (??):

"Older style oxygen sensors actually have a small hole in the body shell so air can enter the sensor, but newer style O2 sensors "breathe" through their wire connectors and have no vent hole. It is hard to believe, but the tiny amount of space between the insulation and wire provides enough room for air to seep into the sensor (for this reason, grease should never be used on O2 sensor connectors because it can block the flow of air). Venting the sensor through the wires rather than with a hole in the body reduces the risk of dirt or water contamination that could foul the sensor from the inside and cause it to fail."

http://www.sjmautotecknik.com/troubl...ic/o2const.jpg

(change 'k' above to 'h' to use link (sjm***********))

I guess that a non direct fit one can malfunction presumably because of a bad splice, if a newer style, restricting the air-flow through the wire. Sounds absurd to me.....but I don't have a sensor to examine. Nothing special from the Denso site about doing this either http://www.densoproducts.com/glossar...nsors?&manID=3

Also, there seems to be little information on why the wild price differences on these simpler 1-wire sensors, plug-n-play or universal-splice. Lots and lots of 'Don't buy Bosch' though, and everyone avoids the dealers, no surprise.

I have found Densos, without the attached factory plug
(234-1057)(universal fit I guess) and can get a pair for under $100.00. The no-names would be about $60.00 for the pair.

My gut says pay the extra for the Densos (quality), but save on average about $20.00 each by doing the splices to the old connectors myself.

donbryce

I found this on another forum:
"DO NOT cut your sensor wires. As stated before, the most critical point is that the sensor feed wire needs reference oxygen to function properly...oxygen feeds thru the wire jacket. The wires to the internals of the sensor are made of stainless steel, not copper, not steel.

If you attempt to solder any of the signal wires, you will clog the air path with the flux from the solder, resulting in failure of the sensor. And, since the sensor puts out millivolts, the connection is critical. Using OEM connectors reduces the possibility of voltage loss and maintains the correct function of the sensor.

Using butt splices is not a good idea as the connection becomes unsealed afterwards, causing potential connection loss. "

FWIW, here's the complete discussion http://forums.corvetteforum.com/c6-t...-or-bad-2.html

Back to the drawing board to search for a good price on Densos with OEM connectors I guess....BTW, I'm in Canada, so bear in mind our prices here are out of sight on these things, and it's very difficult to get reasonable shipping from U.S. parts houses.

yeldogt

If you are not having any problems I would leave them alone.

donbryce

Well, no check engine light or anything like that, but the car has 308,000km on it, and I know the previous owner did not follow the recommended replacement at 50,000mile intervals. I have a '96 Camry, 1MZFE of course, to compare this to, and it is much 'peppier' and gets way better MPG. To top it off, there's oil all over the place around the valve cover/side of engine cyls.1-3-5, and it's on the sensor wire and connector sensor 1 bank1. Given the sensitive nature of the function of these things, I'm betting new ones will improve my MPG, and maybe add a bit of pep to the 'ol girl. I'm doing all the work myself, and it's just a hobby car anyway, so I'm willing to invest a little to see what happens.

I sure wish someone could explain why Denso and Bosch both support splicing the universals, despite what I've read about the dangers of doing this.

Coulter

I'm definitely no expert, but I have a hard time believing that these OEM companies would sell a sensor that was specifically made for splicing, but that it would malfunction if it was actually spliced (as intended)
I think there's a lot of misinformation out there, and I don't blame you for being confused. I had never heard that the outside wires on these O2 sensors "breathed". (I would think that could cause all sorts of issues, especially when you consider how dirty and greasy the engine area can get)

I did a little searching around, and I've heard that it's not a good idea to solder (for possible interference reasons), but to use crimp connectors (and many of these universal sensors come with crimp connectors) I would also think that the "venting" function would only be from the short distance of wires that comes already mounted in the sensor, you wouldn't need that for the entire length of the extension wire back into the factory harness for it to function properly. But again, there's all sorts of different theories about this.

Also, I know it's blasphemy to say this (because we all love our cars), but an 18 year old car with over 300,000 kilometers and is worth probably $2,000 is close to what I would call a beater. You could make a case that nearly EVERY single sensor on that engine needs replacement (MAF, coolant sensor, TPS, etc.) to say nothing of every other component. When I drive a beater, I usually don't go looking for things to replace. If there's no check engine light, and you're not having any real issues, I would seriously consider just driving it as is.

donbryce

LOL....you make some very good points. I do admit to a slight case of insanity when it comes to spending $$ on this car. However, it's my hobby and I enjoy doing the work regardless of the cost...to a point.

OK, now back to the subject. I got hold of the guy at the Denso 'tech line' and discussed this business of how the sensor gets its ambient air oxygen, and whether splicing would be OK. He was adamant that sensors are sealed and don't need/get any oxygen other than what is in the exhaust stream gasses! I didn't argue, just thanked him for his time and hung up. Clearly, if a Denso tech doesn't know how an oxygen sensor works, who can the shadetree mechanic trust?

My sensors in the car have little white holes around the body, and I'm sure these are for the ambient air oxygen needed to produce the voltage signal. I may go to the local parts store and examine one to see if it also has a hole(s) in it for this purpose, or just wait until the Denso universals I ordered show up, in about 2 weeks I'd expect, from CA (Ebay, $94.00 pair delivered). I'm convinced that these will work fine if I do a good splice, which I will detail when they arrive (solder vs crimp). Or, I may look into removing the factory connector and fitting it to the end of the universal wire. Stay tuned....

aneidiaz

Pay for The Densos bro. If thats your gut feeling. I don't think NTK is bad either. I think very highly of anything made from Japan. Great innovative pieces. And very reliably durable. If yu can, go on Sewell Parts and see how much an OEM Lexus o2 costs for your model.