temp gauge

[Jack Broughton]

Have a 2001 S2000 with 62,000 miles, bought it used five years ago and it has operated most satisfactorily with the exception of the temp gauge not totally going to cold position when car has cooled; one bar remains. The upper limit goes to three bars during normal operations and there has never been any indication of overheating. Does not seem to be a serious issue, but just one of those little things that "car guys" find annoying. Any thoughts?

[repiv]

This either annoys certain people or it doesn't. The stock gauge "bars" encompass such a huge range for each segment as not to be that useful anyway, so the fact that one bar always remains is of no consequence to almost all S2000 owners. That 3rd bar on AP1s runs from about 75C to almost 110C (that's 167 to 230 F), so really, if you want a true reading, you're going to have to buy some kind of ECU display so you can see in numerical terms, exactly what the temp sensor sees in the most critical part of the engine. Any other type of add-on coolant temp gauge won't give you a true reading as the sensor must be remotely mounted where the coolant temp is not indicative of what is actually happening.

[Jack Broughton]

Thanks for the reply. Your comments seem reasonable based on the graduated range of the gauge readout. I'll put low bar indicator not "zeroing out" in its rightful place of things to worry about.

[repiv]

Thanks for the reply. Your comments seem reasonable based on the graduated range of the gauge readout. I'll put low bar indicator not "zeroing out" in its rightful place of things to worry about.

I don't think you can "zero out" a temp gauge and that's most likely why that last bar never goes away. Coolant temp can be anything from -40C to +30C, depending on the season and the time of day you first use the car. Just as each bar has its "range", so does the last bar. If you look at most coolant temp gauges that have a needle, when the needle is "pinned" at the lowest point, it's very vague what the actual temp is. There is no standardized temp where such gauges begins.
We can philosophically say that Honda didn't want to eliminate all the bars in the event that we ever see "absolute zero". :D
PS. I have seen the range of the 3rd bar with my ECU display. It's frightening when I come out to my car some days and the coolant temp is -25C.

[Jack Broughton]

By "zero out" in this context, I mean the lowest reading on the gauge scale. Thanks for your comments.

[desmo4]

The temp gauge will read ambient when the car is off and cooled down. If you really interested in the absolute temperature, install an Apexi Imoni, it will display the actual temperature from the obd2 port.

Jonathan

[camoy]

The PLX mutil gauge with the OBDII will also do the same.

[raymo19]

If you'd like a more precise (meaningful) function for your AP1 bar display have a look here:

http://www.modifry.com/products/ect/index.htm

The major differences:

2 bars - Ok for VTEC - 160 degrees
3 bars - 175 to 189 degrees - normal operating temp
4 bars - 190 to 204 degrees - fan should be on
5 bars - 205 to 219 degrees - cause for concern
6 bars - 220 to 234 degrees - Yikes!
7 bars - 235 to ... - Double Yikes!

My personal observations:

This time of year I never see three bars on my 9 mile commute unless I have open road or somebody pisses me off.:D

Summer driving - three bars unless it's really hot and I'm in stop and go conditions. Fans come on at 4 bars and usually cool back to three bars in a few minutes. I've never seen five bars.

Caveat - My car is boosted with the AEM EMS version of this mod. I would think the ECU version map would work just as well for you.

Disclaimer - And no - while I've met Bob I've only bought some of his stuff and don't represent him in any way.:p

[cfloyd]

I have a 2006 S 2000 and I would like to know how many "bars" does the AP1 have compared to the AP2. My 06, while normal driving, goes to what you would call 9 bars which is still a good ways from the half way make on the temp gage. Should I be concerned? Thanks in advance for your responses.

[repiv]

I have a 2006 S 2000 and I would like to know how many "bars" does the AP1 have compared to the AP2. My 06, while normal driving, goes to what you would call 9 bars which is still a good ways from the half way make on the temp gage. Should I be concerned? Thanks in advance for your responses.
AP2 temp gauges are graduated differently than AP1. AP1 normally runs "3 bars". For me, this is between 190F to 204F on a pleasant summer day. I've seen 220F on a really hot, stop and go traffic day and still "3 bars" showing. Only on very rare occasions, have I seen the 4th bar light up. You can run the A/C with the lowest fan speed and both rad fans will always be on. This will aid in getting more air through the radiator and by not running a high interior fan speed, you minimize the heat exchange to the interior and puts less strain on the A/C system. Those who have modified or have eliminated that slanted airguide above and in front of the radiator will regret having done it on those really hot days. There is a purpose to that airguide and that's the time you will realize what that purpose is.
I'll let AP2 owners comment on what's normal, but I seem to recall that 9 bars is about right.

[cfloyd]

Thanks for your response.

[camoy]

Yes 9 is right my AP2 lights nine bars from 179 up it takes 226 to light the 10th bar (I have never done this). I see eight bars when my ECU reads coolant temps up to 178, that 179 causes it to light up the next bar. Normal driving in normal temps 180 is what I am at, on the mountain roads reving it up and holding it in lower gear to keep it in the powerband temps are 200ish.

[repiv]

Note: I have made a correction in my previous post about when the 3rd bar on an AP1 first comes on. I took careful note of exactly what the I-Moni read as soon as that 3rd bar blinked on.

That 3rd bar on AP1s runs from about 75C to almost 110C (that's 167 to 230 F),