L2H2 for $59

[monroe74]

I think that link is dead now. Maybe he went out of business.

But genuine L1H1 do seem to often pop up for under $200.

[mini-e]

Originally Posted by monroe74

"The only way the kit could work is if you soldered to the old or correct plug that had the correct internal connections and resistor"

But I think the point that's being made is this. The old connector doesn't just contain a resistor. It contains a resistor that was calibrated to match that exact sensor.

In other words, I think every L1H1 connector contains a resistor calibrated to match that exact L1H1, and it might not be the right value for some other L1H1 (or L2H2).

So "if you soldered to the old or correct plug that had the correct internal connections and resistor," you wouldn't necessarily be getting a resistor with the correct value.

Would it still work? Probably. How much of a difference would it make? Who knows. It might be the luck of the draw.

I would Imagen that the OEM manufacturing spec is tight enough to insure that the same resistor is used in every assembly in a given revision of the part. Is it worth monkeying around with unknown bits and pieces from potentially different specs? I think not. I would buy the complete assembly as well.

[monroe74]

Originally Posted by mini-e

I would Imagen that the OEM manufacturing spec is tight enough to insure that the same resistor is used in every assembly in a given revision of the part.

But if they were really using the same resistor in every assembly, there would be no need to put the resistor in the connector attached to the sensor. It would be simpler to just put the resistor in the ECU. And if you did that, there wouldn't be any need for a resistor at all. The important thing to understand about the way the resistor is wired is that it's not even connected to the sensor. Both ends of the resistor go straight to the ECU. This is reflected in the fact that the connector has 7 active pins, even though it only has 5 wires connecting it to the sensor. Those two extra pins are for the resistor.

The only reason I can imagine to make the resistor part of the sensor (i.e., in the connector) is because the value of the resistor needs to vary in order to match the exact characteristics of this individual sensor. Basically the purpose of the resistor is to communicate to the ECU the result of a test that was done on this sensor in the factory. As a result the ECU is able to correctly interpret the signals sent by this sensor. Probably this is needed because even if you try to make each sensor exactly alike, they are still going to vary slightly in their pattern of response. It's a precision instrument, and this is the concept of calibration.

This would also help explain why the darn thing is expensive. There's extra labor in the factory to test the sensor and make sure the right resistor ends up in the connector for each sensor.

We could test this theory if we enlisted everyone to test the resistance of the resistor in their L1H1 connector, and post it here. But I don't see that happening.

[mini-e]

That all makes sense. Which means I probably made a mistake maybe someone else can avoid making. When i lengthened my 5 wire o2 (im still going to call it 5 wire to keep from getting cornfused) to reach back to the spot on on the EX exhaust where the primary o2 lives, i added wire between the the o2 and the connector. So i likely added resistance to the circuit with extra copper. I should have lengthened the engine wiring harness out to the o2 connector. that might also be the cause of my "slow to warm primary o2" cel. Thanks for the insight.

Looks like I have a soldering project.

Originally Posted by monroe74

But if they were really using the same resistor in every assembly, there would no need to put the resistor in the connector attached to the sensor. It would be simpler to just put the resistor in the ECU. And if you did that, there wouldn't be any need for a resistor at all. The important thing to understand about the way the resistor is wired is that it's not even connected to the sensor. Both ends of the resistor go straight to the ECU. This is reflected in the fact that the connector has 7 active pins, even though it only has 5 wires connecting it to the sensor. Those two extra pins are for the resistor.

The only reason I can imagine to make the resistor part of the sensor (i.e., in the connector) is because the value of the resistor needs to vary in order to match the exact characteristics of this individual sensor. Basically the purpose of the resistor is to communicate to the ECU the result of a test that was done on this sensor in the factory. As a result the ECU is able to correctly interpret the signals sent by this sensor. Probably this is needed because even if you try to make each sensor exactly alike, they are still going to vary slightly in their pattern of response. It's a precision instrument, and this is the concept of calibration.

This would also help explain why the darn thing is expensive. There's extra labor in the factory to test the sensor and make sure the right resistor ends up in the connector for each sensor.

We could test this theory if we enlisted everyone to test the resistance of the resistor in their L1H1 connector, and post it here. But I don't see that happening.

[monroe74]

Originally Posted by mini-e

im still going to call it 5 wire to keep from getting cornfused

'5-wire' is the normal way to describe it, because it does indeed have 5 wires running between the connector and the sensor. So this makes it easy to tell it apart from the 4-wire sensor that was part of the CA VX in '93-95.

It's just helpful to understand that even though we see only 5 visible wires, there are actually 7 pins active in the connector. And that's because of the resistor housed inside the connector itself.

i added wire between the the o2 and the connector. So i likely added resistance to the circuit with extra copper.

No, I doubt it. Ordinary copper wire (and I'm sure you used some form of that) has very low resistance.

I should have lengthened the engine wiring harness out to the o2 connector.

Even if this kind of wire had high resistance (and it doesn't), it would have been a situation of six-of-one, half-a-dozen of another. The type of wire you used between the sensor and the connector is undoubtedly similar to the type of wire used in the engine harness (with regard to resistance). So I think you're barking up the wrong tree in your assessment that resistance is an issue.

However, there's a different issue that's worth mentioning: shielding. The wires between the sensor and connector are not shielded. But some of the wires in the engine harness are shielded (wires which serve the sensor, that is). So it could be that you have a length of wire that's not shielded, and should be. But I think this would be a very minor issue. It's possible the shielding is there for a relatively trivial purpose (like reducing radio static).

I see you mention above that you realize there might be a problem with shielding.

that might also be the cause of my "slow to warm primary o2" cel.

I don't think the wire you used (type or length) is the cause of this. And I don't have a clear enough picture of your overall setup to make other guesses. But if you describe your situation further, I'm sure someone (me or someone else) will chime in with a suggestion.

[mini-e]

Originally Posted by monroe74

I don't think the wire you used (type or length) is the cause of this. And I don't have a clear enough picture of your overall setup to make other guesses. But if you describe your situation further, I'm sure someone (me or someone else) will chime in with a suggestion.

Instead of the very common y8 on y7 "mini-me performance oriented swap I put a y5 head on a y7 block. the head was port matched to the exhaust and intake manifolds with minor opening of the runners. full radius valve job and a compression bump to 10.3 to 1. I swapped in a 96-m/t engine harness (that was missing the knock sensor wire....which i added). I put in a 98 hx m/t ECU which looked for a pressure sensor on the gas tank- so i changed out the gas tank and filler tube for a 00 ex tank. the ecu looks for the canister purge valve and does not find it, but that does not throw a cel for some reason so for the time being i am using the dx cannister and leaving the purge valve without connection. i put the 96-00 OEM headers on with a 2.5" high flow cat and ex cat back shortened a bit to fit the hatch. I was looking for more performance and better gas millage. which has been achieved. remaining problems...

The aftermarket Hondata thermal isolation intake manifold gasket is having trouble sealing and the nuts have backed off 3-4 times from the 17 ftlb tourqe spec. the recurring vacuum leak causes idle hunting and slight throttle surge from 2k until v-tech (16 valve) engagement which is generally around 3 - 3.3k. depending of throttle position/load. the car runs a little rich based on tail pipe color and plug color and it fights itself a bit at small throttle openings due to this surge. I have also been running with the thermal circuit running from the block to the throttle body to the IACV and back to the block disabled. since I have a cold air intake out to the front bumper my intake temp is ambient. This set-up is yielding about 40 mpg mixed with smooth city driving and 70mph freeway driving. On a warm day on I5 in California I got 43mpg going 70-80. So- not bad, but room for improvement.

I am ditching the Hondata intake gasket. I theorize that the 12 valve mode makes more vacuum that the gasket can deal with. Anyway, I want better millage, so off it comes. I ordered a OEM intake and Throttle body gasket and I am going to hook up the hot water circuit again and let the intake temp go up.

The EX primary o2 location is right in front of the cat. I want to more it to its original HX location, which i believe is much closer to the head. So I will need to remove the header and get a o2 bung welded in and then put the 5 wire where honda put it. I will remove the 3 feet of extension i added between the 5 wire o2 and it's connector.

I am hoping these changes will get rid of the surging and slight rich condition and get me to 45+ mpg. There are not a whole lot of y5 mini-me swaps to reference so I am figuring it out as I go.

the roller rocker assembly sure is cool!!

Thanks for your knowledge.

[monroe74]

There are not a whole lot of y5 mini-me swaps to reference so I am figuring it out as I go.

Yes, it seems that you're pioneering some interesting mods. And you're getting good results. I'm sorry I don't have any other specific tips for you, but thanks for explaining your setup. I also realize now I could have just looked at your garage entry, where you explain some of that. Sorry I didn't do that before I asked. But I enjoyed hearing the details. I hope you keep us posted with your further progress.

[MrChoi]

i got a similar one L1H1 from http://cgi.ebay.com/ebaymotors/ws/eB...MEWN:IT&ih=014

its made by NTK. from my understanding from a lot of research the L1H1 was stock on the 96 to atleast 98 HX. im not sure what year honda made the switch to L2H2 but my 98 HX has the L1H1. its possible the previous owner changed it to the L1H1 but i dont see any reason why he would do that since they cost the same at the dealer. i also doubt this car went through 2 o2 sensor with only 170K miles.

so to recap the L1H1 found on VX's are also found on HX's from factory. L2H2 are an "upgraded" version of the 1 series.