Water Temp Resistor

[blowndodge]

Some of you know that I'm always looking for new answers to problems some of us have ie; pinging and running too hot.

There are many thoughts and ideas. Gadget's site has some from installing a resistor in the air temp sensor to adjusting the TPS or Throttle Position Sensor. I've done them both.

The TPS adjustment did the most for off idle stalling. I've never had is stall since I adjusted it slightly upward.

I added the 1K ohm resistor which eliminated most of the pinging that happpens with the dog sh*t for premium us unlucky folks have on the west coast.

Lately I flushed the radiator and decided that I will never live nor travel into -35 degree weather. I aborted the standard 50/50 mix of coolant to 70/30 distilled water to Low Tox coolant (same green color). Water is far more effective at removing heat than any other liquid. Since the fan kicks on at 212 anyway the 70/30 mixture I'm running won't boil until 230 degrees so boil over shouldn't be an issue and I still have freeze protection to about Zero to -5. The fan always knocks down the temps, even when it was 110 in Lakewood last year.

All of the above have made a noticeable difference. Today was 99 where I live and the fan only came on twice in stop and go traffic which is a lot less than it did before. Usually in hot weather it was on all the time and cooking my legs..

Today afte thinking about it for a good month or more I thought there was even more I could do to keep my Nomad running cooler and thus stronger. I was thinking with 3 sensors monitoring the ECU I had been thinking about adding a resistor to the water temp sensor.

Here's the logic: I rationalized that of all the sensors the really important sensor "might" be the coolant temp sensor. It could be 20 degrees outside and the air temp sensor would be sending that signal to the ECU. Without a signal that the coolant has warmed up the ECU wouldn't lean out the mixture when the water heated up. In my opinion the temp of the water is a more accurate measurement of the heat of the engine. Without the water temp sensor sending signals that the motor is warmed up and the ECU couldn't know to start leaning out the mixture. It would only be getting a signal from the air temp sensor and it's showing its freezing outside! It need to know the water temp too.

This is what the ECU does when the motor warms up. It senses that and adjusts the mixture accordingly. It could do more like change timing too but I don't believe the timing changes with the temp of the air or the water. If you look at the specs in the manual it lists RPMS only as the controlling initital spark lead and total advance. Troubleshooting shows no sensor malfuction associated to timing issues so I just used reasoning?

Anyway about 2 hours ago I spliced in a 330 ohm resistor into the orange wire coming out of the water temp sensor plug. The manual shows the following resistance values at these water temperatures measured in F:

68 = 2.161-3.112K ohms.

122 = 0.785-1.049K ohms

212 = .207-.253k ohms. Temp when the fan kicks on.

As you can see at the time the fan kicks in is the least resistance value to the water temp sensor.

Adding a .330K ohm resistor will fool the ECU into thinking that the engine is cooler and thus not lean out the mixture as far as it would have at 212F Now the sensor will max out at:

.537 - .583K ohms at 212F . The motor will think the coolant is at about 155 - 175F according to my calculation since the sensor isn't reducing it's value in a linear fashion. In other words the higher the water temp becomes the less and less the resistor value decreases.

The reason I didn't try to "fix" everything with the air temp sensor is that going too far with either sensor will show a "red eye fault" when the motor is cold when first starting up. Both resistors don't put the "start up value" outside the parameters set up in the ECU. I wanted to push all the values in the sensors as close to the max allowed in the manual and not show a fault code.

I ran the bike but didn't go but 5 miles just to see if the fault light would come on and it didn't. Tomorrow is suppose to be super warm again and I will try to make it ping when it's all warmed up and hopefully the water temp resistor is doing it's job!

No worries about the fan not coming on. The water temp sensor that controls when the fan kicks on is located at the bottom of the radiator and is not affected.

I like the philosophy of distributing the changes over the available sensors.

This is basically how a Power Commander was originally designed to work. It fooled the ECU into thinking the sensor values were different than what they actually were, and the ECU delivered more or less fuel accordingly.

330 ohms actually seems a little high to me, but we'll know more when you actually test it.

[blowndodge]

Lets say your right, it wouldn't be the first time, and it is a little high? What would you do?? It's obviously to me. I would downgrade my gas! Try mid grade and/or regular?

Or........take out air temp resistor and just leave the water temp resistor in.... I know you and I don't have any issues with splicing wires!!! ..

You could try low octane & if it doesn't ping, see if the mileage improves too. Then you've accomplished something impressive for sure.

Or, maybe leave it and try a smaller value in the air temp circuit. Maybe half what you're running now.

Fooling the sensors with too much resistance makes their aparent output (aparent to the ECU that is) more linear than original. By spitting the business between two or three sensors you minimize that effect. I think that's good. I don't think you want it to be too linear.

[ringadingh]

I would think that if you could retard the timing a couple of degrees, that would cure the pinging more so,rather than adjusting the fuel injection system,which is basically changing it either rich or lean, this doesn't always cure the pinging as does the water temp. I dont know if the timing is adjustable on our bikes,to try this. Also if you put in a thicker,or double head gaskets, that may lower the compression a bit, so it cures the pinging. Both of these procedures would lower your performance very slightly. The best procedure may be to change the advance curve in the timing, but that is in the ECU, and I don't think they are programable.

[blowndodge]

Update:

Took the Nomad out for a longer ride today. It's still really warm here about 90. Not sure if my mind is playing tricks on me but the bike started real easily. Not that it didn't before but is was like Ka boom and running.

Ever notice that when you make a turn at an intersection, like a right handed turn in first gear with the throttle barely on you get a sense of a slight surge? Know what I'm talking about? It makes completing the turn hard to do smoothly without having the right hand of a surgeon.

It doesn't seem to do that and again, could be the weather? Not sure. Took me forever to get it hot enough for the fan to come on but it finally did. Tried to goose it a few times and I still can get a light ping out of it but it only last for a second then stops, like in a narrow rpm span 2000-2500 range. Once through that range and banging the gears there is nothing.

Not the "total cure" I was hoping for but I had to try it. My seat of the pants tells me there is no off idle surge anymore. Just felt real smooth at very small throttle openings.

Unless you really crank the mixture up and kill some of your mileage I think Ringadingh might be right and the timing is going to be the hang up in solving all traces of pinging.

[ponch]

If the bike had a true closed loop system, it would have a knock sensor and adjust the timing. Such is not the case. The system is limited and there is only so much you can do to fake it into running differently. Without better feedback like an O2 sensor and and a knock sensor, I have to wonder if it is worth all the hacking. A better question is, if cars have had this for years, why not bikes? Some do, like the BMWs. They even have CANs.

Originally Posted by Ringadingh

I would think that if you could retard the timing a couple of degrees, that would cure the pinging more so,rather than adjusting the fuel injection system,which is basically changing it either rich or lean, this doesn't always cure the pinging as does the water temp. I dont know if the timing is adjustable on our bikes,to try this. Also if you put in a thicker,or double head gaskets, that may lower the compression a bit, so it cures the pinging. Both of these procedures would lower your performance very slightly. The best procedure may be to change the advance curve in the timing, but that is in the ECU, and I don't think they are programable.

Well, Ponch I can only say: "If yer aunt had balls she'd be your uncle."

What we got is what we got; and that's all we've got to work with.

So if we want them to run better, hack we must.

[blowndodge]

My girl bought a new at the time 2005 Ford Escape and when it was new you could run coolaid in it and it fan fine. Now with some time it pings some on regular. Most of your Joe Average cars today are made to run on regular and they do not have a spark sensor.

The cars that come with a spark sensor tend to be high performance and have one so you can run regular at a slightly reduced performance level.

[ponch]

That's true, but today, they can fix the uncle/aunt conundrum. Years ago, you could fiddle with timing, jetting, different carbs and intakes, etc. Today, they are made to run in a narrower spectrum and if you want to fiddle, you have to hack. Even for this computer guy, I get tired of the technology. Sometimes I am just happy the damn thing works anymore. :) If I want speed, may be I will just get a C14.

Originally Posted by caddmannq

Well, Ponch I can only say: "If yer aunt had balls she'd be your uncle."

What we got is what we got; and that's all we've got to work with.

So if we want them to run better, hack we must.

[ponch]

I can't speak for what ford does, but my VW runs on piss with a higher compression than the Nomad. That thing has more computer controls than Data on star trek.

Originally Posted by Blowndodge "Darksider"

My girl bought a new at the time 2005 Ford Escape and when it was new you could run coolaid in it and it fan fine. Now with some time it pings some on regular. Most of your Joe Average cars today are made to run on regular and they do not have a spark sensor.

The cars that come with a spark sensor tend to be high performance and have one so you can run regular at a slightly reduced performance level.

Originally Posted by ponch

That's true, but today, they can fix the uncle/aunt conundrum....

Yes they can, but you don't wanna know what that would cost (that is if you don't want a hack job. LOL)

It would make custom-built fuel injection look cheap.

[bobzinger]

How about something like this with an O2 sensor. Of course they don't make it for the 1600 Kawasaki's yet and it's $500. Here's one for 1500 Classic.
http://www.terrycomp.com/ProductDetail.aspx?ProdID=73

Ya know, I was checking out Terry's website and there's a serious dearth of info regarding the metric applications. Lots of info if you own a Harley though.

Maybe I'll send them an e-mail & see what they'll tell me.

[rewindgy]

I would be very interested in what he has to say!