engine oil temp sensor

[dlaing]

That is precisely what I intended to say, Dan talks about the sensor itself. Did you? I did start by asking what charts you refered to.

 

Are you still talking about sensitivity, and not accuracy? We have been shown that we can move the point of "largest slew" with the bridge resistor, but we can't move the point where the sensor is accurate.

I have talked about both.

The disagreement is about the comment on the sensor itself, but in the real world, it is how the ECU interprets it that matters, so both are relevant.

Sorry, I have not been clear enough.

According to the chart you posted, both the volts after bridge resistor and the PERCENTAGE difference in Ohms, before resistor, for every ten degree change in temperature, we see the greatest difference occuring between 30 and 40° and the lowest differences as we approach the outer temperature limits, both high and low.

 

It is not an even curve of "difference"

 

The difference does not correlate to accuracy but it does correlate to sensitivity.

 

Usually with greater sensitivity you find greater accuracy.

 

I am arguing about sensitivity not accuracy, because that is all we can determine from that chart, and that is the word that Dan chose in the statement that was disagreed with.

 

From the chart between 90 and 110 we get an unexceptional change in voltage or ohms.

Between 30 and 50 we get the greatest change, which supports Dan's argument if he moved the curve to the temperature range spec'd for 5% W/°C accuracy from -40 > 125.

Of course how often are we riding below 0C???? So, I can see why Dan assumed they would make the accuracy center on nominal driving temps.

 

Certainly if people in this thread, myself included acted with greater sensitivity and reacted with less sensitivity, we would have greater accuracy in pinpointing the disagreement and we could shorten the discussion by ten pages or more

[dlaing]

I predict the Dow will bottom out at 4,000 about the time that this topic'll reach 40 pages. Coincidental? Only the philistines know for sure . . .

If it hits 4000, it would bring a whole 'nother meaning to

Dow of Poo

[Skeeve]

 

Hey, your graphic misspelled "Tao!"...

[Guest ratchethack]

Thanks Ratchet.

The more I think about it, the more I like your strategy.

Careful, Dave. It's a high risk proposition, you know.

 

It might cost you fifty cents, or even as much as a dollar to try out the heat sink.

 

. . .And there are those hereabouts who wouldn't approve a-tall if you happened to post overwhelmingly positive results. . .

 

Here's a local electronics liquidator:

 

San Diego Electronics Supply

8148 Ronson Rd., Ste. E

858 278-1245

 

If you jawbone the proprietor a bit, and buy something else, Manny might throw in a heat sink identical to the one he threw in gratis (it fits perfectly after a 45-degree chamfer in the mounting hole) with the 1K Ω variable resistor I got from him (with the knob) for $2.

 

BTW: He's open Saturdays.

 

EDIT: by popular request via PM (you're welcome), here's the Mfg & P/N on the heat sink I wound up with, though there are probably dozens, if not hundreds of alternatives that would work as well:

 

IERC

UP2-T066-52

[Guzzi2Go]

I see that this thread made quite an advance recently (in terms of number of posts, advance in terms of general understanding what is going on is somewhat limited). Unfortunately, I am a bit pressed for time (traveling a lot lately) so I'll try to keep it short/quick.

 

If you experience high fuel consumption on cold days, you MAY try to improve thermal contact between sensor and engine.

 

If you do that, you MAY experience symptoms of running lean (like pinging).

 

If you do experience these symptoms and have a possibility to alter map (myECU, PCIII), you SHOULD fix the map (real solution).

 

If you don't have the possibility to fix the map, you MAY add a resistor in series to temp sensor. Values in the range of 100-500 ohm seem appropriate (band aid).

 

If you add big enough heatsink to your engine temp sensor you will turn it into air temp sensor. You SHOULD NOT do that.

 

If you replace plastic sensor adapter with a brass one it will have the same effect as adding heatsink to the sensor. You SHOULD insulate the brass adapter.

 

If you increase air gap between engine and sensor, you will make it more sensitive to ambient temperature. In an extreme case, you will turn it into air temp sensor. You SHOULD NOT do that.

 

 

And yes, for those not sincerely interested in neither Philistines nor Bohemians, thus not willing to read the exceedingly long rant about them - Philistines = Palestinians, Bohemians = Czech.

[Guest ratchethack]

. . .And then there are those who, apparently unable or unwilling to read, would be so presumptuous as to dictate to others exactly what they SHOULD and SHOULD NOT do (repeatedly at that), and inform others what will happen -- based on evidently (in the case of both heat sink and resistor) no actual experience whatsoever, without qualification, regardless of engine config., or map, and regardless of whether or not addition of thermo-compound helps a specific rich condition or aggravates a specific lean condition, creating unrideable symptoms, etc., straight across the board -- as if what works best for one must work best for all, and as if what doesn't work best for one can't possibly work well for any.

 

. . .[sigh]. . . and waddayagonna do?

If you don't have the possibility to fix the map, you MAY add a resistor in series to temp sensor. Values in the range of 100-500 ohm seem appropriate (band aid).

In English, this reads a lot like you're granting permission, G2G. Was I "incorrect" for having jumped the gun in advance of your OK? Do I have your permission to use a 1K Ω variable if I promise to only use half the scale?

 

And yes, for those not sincerely interested in neither Philistines nor Bohemians, thus not willing to read the exceedingly long rant about them - Philistines = Palestinians, Bohemians = Czech.

Hm. For someone "not sincerely interested" and "thus not willing to read" particular posts, there seems to be quite a remarkable interest in taking the time to critique what you haven't read.

 

How does that work?

 

And if you're "not sincerely interested" and "thus not willing to read" particular posts, why would you give a flyin' fark in a rolling donut how long they are -- let alone go to the effort of repeatedly posting complaints?!

 

Enquiring minds. . . (well, you know). . .

[dlaing]

If you experience high fuel consumption on cold days, you MAY try to improve thermal contact between sensor and engine.

 

If you do that, you MAY experience symptoms of running lean (like pinging).

 

Been there, done that (at least that was my experience after putting thermal paste between sensor and Brass Adapter.

 

If you do experience these symptoms and have a possibility to alter map (myECU, PCIII), you SHOULD fix the map (real solution).

 

If you don't have the possibility to fix the map, you MAY add a resistor in series to temp sensor. Values in the range of 100-500 ohm seem appropriate (band aid).

I actually want to do both. The readings on my Wide Band Oxygen Sensor are difficult to read, but if I have a rich/lean switch, I could flip i t and see how the reading shifts, helping to eliminate issues that give false readings. For example it may read lean because of incomplete combustion, not because it is too lean. A flick of the switch with intelligent observation could get past that analysis.

 

 

If you add big enough heatsink to your engine temp sensor you will turn it into air temp sensor. You SHOULD NOT do that.

That would be one big heatsink!

What I would like to know is how much of the reading is effected by heat at the tip of the sensor and how much of the reading is effected by heat at the body of the sensor.

Trial and error I suppose. It would be good to hook up a volt meter to the sensor output and observe the output. Something an 8th grader could do, but I am lazy....

 

If you replace plastic sensor adapter with a brass one it will have the same effect as adding heatsink to the sensor. You SHOULD insulate the brass adapter.

Is this statement meant as bait?

They have the opposite effect.

The brass sensor actually transmits more heat to the sensor.

The heatsink pulls the heat away from the sensor.

I initially wrapped a good amount of teflon tape around the threads of the sensor, but many on the forum said it would not get too hot, so I removed the tape and added paste, and I don't think it has not run as well since. I don't think I noticed at first since it was tuned and had a rich map installed, but a little out of tune and it acts up.

Ratchet's posts helped reinforce my suspicion.

Still I need to re-insulate at the threads, not the tip.

But getting some bonafide voltage readings is really the way to go.

 

 

If you increase air gap between engine and sensor, you will make it more sensitive to ambient temperature. In an extreme case, you will turn it into air temp sensor. You SHOULD NOT do that.

Yep!

 

And yes, for those not sincerely interested in neither Philistines nor Bohemians, thus not willing to read the exceedingly long rant about them - Philistines = Palestinians, Bohemians = Czech.

Is that a triple negative?

vs.

http://www.taybehbeer.com/

[GuzziMoto]

Don't be bustin' on Naty Boh, Hon.

 

 

 

 

 

 

 

 

It's a B'more thing.

[Greg Field]

Unless you insulate the brass temp sensor, it will act as a heat sink, as G2G said and as revealed in this post, back in '06:

 

http://www.v11lemans.com/forums/index.php?...t=0&start=0

[Guest ratchethack]

Been there, done that (at least that was my experience after putting thermal paste between sensor and Brass Adapter.

. . .

What I would like to know is how much of the reading is effected by heat at the tip of the sensor and how much of the reading is effected by heat at the body of the sensor.

Trial and error I suppose. It would be good to hook up a volt meter to the sensor output and observe the output. Something an 8th grader could do, but I am lazy....

Trial and error -- I b'lieve you might be on to something here, Dave!

 

It'd be one alternative to the more ideal laboratory setup with a brake dyno in a wind tunnel, and a brace of diagnostic gear connected via a long tangle of cabling and wires -- should you happen to have such a collection of gear handy.

 

Lacking that, for yourself, and perhaps for others experiencing hot over-lean symptoms at idle after installing thermo-compound, as I did myself until it disappeared completely over a week ago, I suppose you could spend weeks of trial and error doing experiments with both plastic and brass sensor holders with every possible combination of thermo-compound, air gap, and heat sink, chasing a hands-on understanding of the dynamics of heat flow involved, and figure out how the thermistor read is distorted at the tip of the sensor by the unwanted influence of the relatively massive sensor body. This could provide you with a fair grasp of how the inherent THERMAL INERTIA of the sensor body is the big culprit here.

 

Then you might decide to proceed to discover how nicely and how thoroughly a 1. heat sink and/or 2. variable resistor actually functions to both 1. overcome and/or 2. compensate for (respectively) the inherent error it sends to the ECU by actually demonstrating it to yourself on the road.

 

BUT HEY, LOOK! Somebody already "claims" to've done this, and has comprehensively documented (and updated) the whole extravaganza -- by sub-topic heading, at that -- waaaaaaaaay back in post #280 on page 19 of this very thread!

 

Now this all seems to've been gibberish to those not sincerely interested enough to actually read it, but who've nonetheless not hesitated to offer their criticisms of what they haven't read (as expected ), and I suppose any psychotic nut log could've imagined the whole thing in some deluded episode of wishful thinking (as has actually been suggested).

 

Maybe it's merely a great walloping pile o' fraudulent, unfounded claims that were intentionally dreamed up, simply for idle Winter amusement, the equivalent of dragging a great reeking wagonload o' fresh horse pucky through the middle o' this here Forum for the sheer enjoyment of fielding the expected caterwauling of protest in its wake -- and to flush out the most prolific sources of bellowing and whimpering. . . I concede that yes -- to a proper objective analysis, this could very well be the case here. . . and your previously expressed skepticism IS most certainly well-founded!

 

On the off-chance you become convinced of such lunacy, deceit and chicanery^ as a result of your own testing and findings to the contrary under the same or similar documented scenario, I reckon you'd be obliged to expose the aforementioned documented study as a fraud -- or at least post your contrary results, strenuous objections and/or advice to others based on actual experience optional, but at least with some basis for such objections and/or advice.

 

Or being lazy (noted), you might hire an 8th grader (or an 8 year-old, for that matter) to whip up something for you. . .

 

Or, you could skip the above, take a great walloping $1 or $2 plunge, and give Manny a call (see post #409). Wot kind of an effort d'you figure it takes to have your head temp sensor/holder out and back in again?

 

NOTE: The heat sink on mine makes a pretty good handle for removing and installing the sensor and holder. Truth be told, since the start of my experiments, with or without heat sink installed, I can have it out with or without a 19 mm wrench in about 15 seconds, and back in, in about the same.

 

HINT: You can easily put "ramps" on the "retention nubs" on the AMP connector at the sensor with a file, so it can be easily, repeatedly (and securely) popped off and back on again without the fuss of fiddling with the 1-way retainer clip.

[dlaing]

Then you might decide to proceed to discover how nicely and how thoroughly a 1. heat sink and/or 2. variable resistor actually functions to both 1. overcome and/or 2. compensate for (respectively) the inherent error it sends to the ECU by actually demonstrating it to yourself on the road.

 

BUT HEY, LOOK! Somebody already "claims" to've done this, and has comprehensively documented (and updated) the whole extravaganza -- by sub-topic heading, at that -- waaaaaaaaay back in post #280 on page 19 of this very thread!

Your work is appreciated, but the results are based on controversial theory and seat of the pants observations.

 

My situation is different. I ordered the plastic adapter years ago and it still has not arrived, so I am stuck with the brass adapter. Some say it makes it run richer, some say it runs leaner. Whatever, I'll stick to my view that more heat is transmitted through it, but I will agree that the brass adapter may run richer if the ambient conditions cool the adapter faster than the engine, in conditions such as high speed and or rain.

The heat sink you added will exasperate any wind speed and weather related changes at the sensor.

How much it exasperates the situation is unknown, but like anything it can be theorized that the heat sink is lowering the sensor reading more under conditions where you would want less lowering.

Because of that theory, I initially rejected your idea of adding a heat sink, but on further thinking it, I am open to the idea that when the sensor tip is immersed in conductive goo, the reading MIGHT be more "consistent" when you add a heat sink.

My situation is also different because I have tuneboy.

I want to know what the sensor reading is when I get bad running. Is it off the chart (above 125C)? If it is off the chart, my re-mapping could be futile and a heat sink might be a good idea. If it is on the chart, whatever the point of rough running is, that is the point in the map where I could modify it.

My initial idea is to insulate the sensor at the threads with teflon tape, but that is limited insulation and your heat sink idea may still prove valuable, even with the brass adapter.

[Guzzi2Go]

Your work is appreciated, but the results are based on controversial theory and seat of the pants observations.

So you noticed that too. Funny how it seems the method to be acceptable now, when offered by "yours truly" and ridiculed when offered by someone else.

...

Because of that theory, I initially rejected your idea of adding a heat sink, but on further thinking it, I am open to the idea that when the sensor tip is immersed in conductive goo, the reading MIGHT be more "consistent" when you add a heat sink.

It might, but it won't. I guess it all depends on the thermal inertia of the goo.

 

My initial idea is to insulate the sensor at the threads with teflon tape, but that is limited insulation and your heat sink idea may still prove valuable, even with the brass adapter.

That would be the same as adding an air gap (+ optional heatsink). Hard to get consistent results using that technique. Insulation MUST be applied on the outside of the adapter.

[Guzzi2Go]

...This could provide you with a fair grasp of how the inherent THERMAL INERTIA of the sensor body is the big culprit here.

WOW! Just how big of a culprit is it actually? How about a model, explanation, calculation, interpretation? What to hell, you can even throw a fistful of Philistines in the equation if necessary...

 

Analytical mind....(well, you know)....

[Guest ratchethack]

Your work is appreciated, but the results are based on controversial theory and seat of the pants observations.

Dave, I've posted observations based on what I've actually done and tested myself, nothing more. The laws of thermodynamics are only a "controversial theory" to those who've never studied them, and therefore haven't got the first clue about the difference between a theory and the fundamental laws of Physics. If you believe I've posted some other "controversial theory", please show me where.

So you noticed that too. Funny how it seems the method to be acceptable now, when offered by "yours truly" and ridiculed when offered by someone else.

G2G, please show me exactly where I've ridiculed anyone's post of any valid personal hands-on experience of their own on this thread.

How about a model, explanation, calculation, interpretation?

If you'd read what I've already posted and referenced several times above, you'd have found not only well documented explanation interpretation, but a first-hand, experienced-based analysis clearly laid out in sub-topic with BOLDED CAPS. You'd also have been hard pressed not to notice that I'd very carefully and very specifically DISCLAIMED the exact limits of what I did and observed, and even indicated what specific analyses and methods I DID NOT DO -- nor claim to have done. Any rational person would acknowledge that the lack of use of specific analysis gear does not disqualify valid testing results on the road, and that no measurements nor calculations were needed to arrive at the results as I clearly presented them.

 

You STILL seem to be missing the glaringly obvious fact that you haven't documented any first-hand experience whatsoever upon which to base your incredibly presumptuous orders specifying what people SHOULD and SHOULD NOT do, and what WILL and WILL NOT happen, nor any reference to anything supporting such baseless orders and groundless prognostications.

 

If you believe that I've done the same thing myself, please find an example and quote me word for word, as I quoted you in the examples I provided above.

 

WARNING: If you attempt to do this by taking my words out of the clear and obvious intent of the context as presented in my posts, I will not hesitate to put them BACK INTO context exactly as posted -- and this could make it fairly obvious that you suffer from deluded perceptions, and/or one horrific reading comprehension problem.

 

Now if you have any personal experience whatsoever upon which to base your orders to others on the addition of a heat sink and/or resistor, or any other credible knowledge base as a reference (as I've quoted you above), please also show me where you've posted your personal experience or reference to that credible knowledge source.

[luhbo]

..... Whatever, I'll stick to my view that more heat is transmitted through it, .....

 

Hold on David, hold on. Just for a moment.

 

Have you ever looked at the picture that Greg has posted several times now? Have you ever seen it? Not the light, the picture

 

Think about that, for a short moment only, do me the favour, and then you may catch up again to this furious stampede.

 

Hubert