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O2 sensors for Regina 700

Regina may be a sweet ride, but she isn't a cheap date.

There is talk in the FAQ about generic Oxygen (lambda-sond) sensors in LH cars, but no mention of Regina there at all. I believe I have read in the past that the Regina system uses a completely different type of sensor than the others.

Can someone explain to me the difference and ideally tell me that there is a generic substitute for the expensive direct fit. I want to replace mine just because I don't know it's age or condition.

Thanks (as always) in advance.

Andy in St. Paul
'91 745 Regina 186K, '89 244 136K (currently running too rich), '87 245 lost the rust battle at 225K
--
Andy '91 745 184K, '89 244 135K, '87 245 lost the rust battle at 225K mi








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    O2 sensors for Regina 700

    Check out this site:

    http://www.discountconverter.com/O2Sensors/

    They seem to have a great selection of oxygen sensors. I have no first hand experience with Zerconia sensors, but let me add some food for thought.

    On the above site, they offer a 3-wire zerconia sensor for both Volvo and Jeep (the Jeep's is half the price of the Volvo). You may want to research this, because they may be the same sensor with simply a different plug.

    Case in point: My '92 Mercedes takes the exact same sensor as a Ford 302 V8. The only difference is the connector, and the cost. The MB part is 3 times the cost of the Ford part (both made by Bosch)

    So what enlightened Mercedes owners do is buy the Ford sensor, cut off the connectors on both sensors, then solder/shrink wrap the MB connector to the Ford sensor. And you save yourself $100.

    Again, I don't know that the Jeep part will work the same way in a Volvo. But it's worth investigating. If you find that it is the case, it would be a major victory for all BrickBoard members with Regina Ignition systems. Post back if you discover something.

    Good luck,

    Jeff Pierce
    --
    '93 945 Turbo ( one kickass family car ! ), '92 Mercedes 190E (my daily driver), '53 Willys-Overland Pickup (my snow-plow truck/conversation piece)








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      O2 sensors for Regina 700

      Thanks Jeff.

      I think I need to stop and make sure we are all talking about the same things at the same time, though. Here is what I understand from my research and what I've read here on the board.

      The Bosch LH systems use the Zirconia (voltage generating) sensors. These are more common and are available for $40 or so.

      Some have been saying that the Regina system uses the Titania (resistance generating) sensors. These are rarer and I have seen several sites listing them for Jeep, Nissan, etc, but no documentation of Titania for Volvo at all.

      If Regina uses Zirconia, then Groton is right and the regular, generic, three wire should work.

      I may have some of this wrong and will welcome any corrections.

      Thanks to everyone for your experience and opinions. I agree very much that it would be stupid to pay many dollars for the "right" plastic plug when a careful splice will do. Besides, the practice of manufacturers each making their own plug style and even changing it every few years, only to make them unique and expensive, is quite unfriendly.

      Andy


      --
      Andy '91 745 184K, '89 244 135K, '87 245 lost the rust battle at 225K mi








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    UPDATE - O2 sensors for Regina 700

    The O2 Sensor info from Artemus (copy below) does NOT apply to the Regina FI System.

    Google NGK. They have a part finder that can give you a generic part number for your vehicle.
    I drive a 1990 740 GL Rex/Regina and the number for my O2 sensor is 25063.
    I found one at clubplug.net for $58.08 plus $5.00 shipping.
    Please reseach to make sure you get the right part for your particular car.


    I talked to NGK Tech Support, and the 25063 sensor is for a TURBO, and thus applies to the Bosch FI. It will not work in a Regina car.
    BTW, $58+ for a $39 bosch type 3-wire sensor sounds pricey to me.

    NGK does list a Titania sensor for a 940 na, with a "suggested" list of $236 (P/N 25002), but I couldn't find it on the clubplug.net site. So the FCP price of $140 or so may be as good as it gets.

    (Too bad Artemus isn't registered so I could get this on his email.)
    --
    Bruce Young,
    '93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.








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      UPDATE - O2 sensors for Regina 700

      Thanks, Bruce for saving not only me, but maybe Aremus and a lot of others from a costly mistake.

      I am still going to call Groton, though, because I know them to be quite honest and they will want to change their listing for a generic that implies it would fit the Regina cars.

      Andy
      --
      Andy '91 745 184K, '89 244 134K, '87 245 lost the rust battle at 225K mi








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        UPDATE - O2 sensors for Regina 700

        You're right about the FCP listing, Andy. Even though the "direct fit" applications do distinguish Bosch vs Regina, the "all 85-92 models" at the bottom is misleading.
        --
        Bruce Young,
        '93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.








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          UPDATE - O2 sensors for Regina 700

          I made a new post of this so that it would get noticed, but I thought I shoudl put it here too in case you were watching this thread. Andy

          _______________________________________________________________________

          I posted last week asking if it was true that the Regina system used a completely different type of O2 sensor than the Bosch systems. The replies were that, yes, Regina uses a "titania" sensor and the generics will not work.

          I called FCP Groton since their site lists a generic walker for ALL 740s including the Regina years. They assuree me that their $49 Walker generic works with Regina.

          Frankly, I don't know who to believe, so I'm hoping for some more input. If Groton is right, I want to save a lot of money. If they are wrong, then I'm sure they will change their listing if I can convince them.

          Andy in St. Paul
          '91 745 Regina 186K, '89 244 136K, '87 245 lost the rust battle at 225K
          --
          Andy '91 745 184K, '89 244 135K, '87 245 lost the rust battle at 225K mi








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            UPDATE - O2 sensors for Regina 700

            Jeff Pierce (tvpierce) recently made a great reply about GRAFTING a sensor into the system.

            Lots of people are doing this.
            Why?
            For the very reasons that Jeff either noted or implied:

            1. Most sensors have the same mounting format: threads, etc.

            2. Within families (or TYPE; Titania, Zirconia, Kryptonite or whatever) they work on the SAME principle, whether for for Kia or Mercede$, for instance.

            3. They vary A LOT in price; i.e. Kia tends to be < Mercede$, right? ;-)

            4. They vary by LENGTH of leads (the wires; typically 3, or 4 [newest] ... even 1 for oldest) and the CONNECTOR at the end of the leads.

            5. So? No big deal: cut and splice to save money!

            I slogged through an entire 500-page (IIRC) Bosch oxygen sensor manual to look for the drift of all this (and more): Yup, I could SEE that the Corolla sensor that I just replaced on my wife's car had a VERY different MOUNTING FORMAT, just as I saw in real life.

            But something like 90% of sensors shared the same mount, and varied only as I said above.

            I hope that makes sense.

            Andy, I live in Mpls, if you want to drop by and borrow the Bosch oxygen sensor book, or solder in a new sensor together. Easy.
            --
            Gregg in MN








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    O2 sensors for Regina 700

    Hi all:

    Google NGK. They have a part finder that can give you a generic part number for your vehicle.

    I drive a 1990 740 GL Rex/Regina and the number for my O2 sensor is 25063.

    I found one at clubplug.net for $58.08 plus $5.00 shipping.

    Please reseach to make sure you get the right part for your particular car.

    Good luck,
    John








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    O2 sensors for Regina 700

    I haven't had to replace mine yet (not quite a year on the 940), but did do some O2 sensor research. Bottom line—the Regina sensor is different.

    It uses a "Titania" sensing medium, which changes resistance according to the amount of oxygen detected.

    The Bosch-type sensor uses "Zirconia", which generates a small voltage depending on the oxygen sensed.

    Do a Google search on titania for more info. It's a good sensor, and doesn't need access to ambient air like the Bosch. For this reason it is used on some Jeeps and other potentially off-road vehicles. So there may be hope for a cheaper version.
    --
    Bruce Young,
    '93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.








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      O2 sensors for Regina 700

      I don't know the answer to this, but if anyone hears accounts of success substituting the zirconia sensor, there may have been some choices made by Bendix to make it possible.

      Just suppose, the midpoint of their comparator remains at 1/2 volt like the Bosch ECU, _and_ they've chosen the current applied to the titania sensor to result in a similar voltage curve, i.e. 0-1V, _and_ the current imposed to read the titania sensor has a negligible affect on the voltage developed by the zirconia sensor which is not open circuit in lean mode once warm, then perhaps a Bosch could do in a pinch. Of course, without the advantages offered by titania sensors as you noted. And it might explain the "universal" designation for replacement.

      Just a theory, though a Saturday afternoon with a Regina car might disprove it.








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      O2 sensors for Regina 700

      Thanks for that info. It does give me a lot to go on.

      FCP Groton lists a specific sensor for Regina, but then they list "Universal 3 Wire Oxygen Sensor will fit all 85-92 models". That must be wrong. I think I will call them and ask about that. They may want to change that.
      --
      Andy '91 745 184K, '89 244 134K, '87 245 lost the rust battle at 225K mi








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    O2 sensors for Regina 700

    Sorry, I can't shed any light on the O2 sensor situation.

    Have you done things like read out the fault codes and measured the fuel pressure in an attempt to isolate the cause of your richness, so that you don't start purcha$ing unnecessary part$?

    When it comes to forking-out the extra dough for Regina parts, just keep telling yourself things like "Only one fuel pump to go bad" or "No expensive Air Mass Meter!"

    Good luck.







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