ECT2 & ELD question

2012+ US/Canadian Civic Si / 2013+ ILX
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Burban1880
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Joined: Tue Nov 10, 2020 8:36 pm
Location: Ohio

ECT2 & ELD question

Post by Burban1880 »

I have a 15 civic si that I have my wideband wired to the ecu so the flashpro can read it.
What or how does the ecu handle the ect2 or eld when they are disabled in flashpro?
It is to my understanding that the ect2 controls the on/off function of the cooling fans. Also the eld handles the charging side of things. So if either or is disabled that particular function is obsolete?
EFICU
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Re: ECT2 & ELD question

Post by EFICU »

The ELD function should be turned off in the tune IMO anyways. I have seen fueling issues, especially at idle with ELD enabled. With it enabled, and fuel economy alternator, those fueling scenarios go off track and cause a number of seemingly minor but annoying issues.

ECT2 does not control fan operation, ECT2 is the temp sensor after the radiator. ECT1 is the sensor that controls fan operation.

Most the guys I've helped who wire the wideband in use ELD.
Burban1880
Posts: 5
Joined: Tue Nov 10, 2020 8:36 pm
Location: Ohio

Re: ECT2 & ELD question

Post by Burban1880 »

I have my wide band wired into the eld and had forgot to disable it once. Like you said it gave me a bunch of annoying issues especially with the fueling.
I am to assume though that with the eld disabled, the alternator is in a continuous charge state? Or does the ecu default to something else eg.voltage regulation? What happens with the ECT2 input?
Huh that is weird because I thought ECT2, which is by the radiator did control fan operation. ECT1 is the sensor off the head.
The only reason I thought that was because when I set the fans to turn on at say 194*F, ECT in Flashpro would display 212*F while ECT2 would display 194*F upon fan operation.
I am just curious to what happens to either sensor when disabled in flashpro from the ecu operation standpoint.
Thank you EFICU for the help.
EFICU
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Re: ECT2 & ELD question

Post by EFICU »

Yeah when I first got into working on 9th gens I had trouble figuring out why the idle fuel would suddenly go weird and other various fuel issues. Then after testing the ELD and fuel economy alternator disabled those issues went away. I suppose in the grande scheme it isn't too big of an issue, but it sure drives you nuts when you're tuning them and things are all over the place. I couldn't tell you the technical details on the charging state, but if you watch the battery voltage with them enabled you can see it's all over the place, and when it dips below 14v things go out of wack.

You will sometimes see a variance in ECT1 to ECT2 of up to say 50*F, if ECT2 told the ECU when to turn on the fans at 194, that would mean the coolant in the engine would be 244*F. I don't think Honda wants the coolant in the engine to be that hot. When it goes by ECT1, it will turn on when the engine coolant temp gets to 194 in your case. I have seen the temps get high like you say on ECT1, but it could be how quick the cooling system can pull the heat from the system depending on the temperature of the day. Think about it too, if Hondata gave you the option to disable ECT2, and that controls your fans, things would go wrong very quick. Also, if you open an 8th gen calibration file, you will see those have the option to use ECT2 for fan control. Which you would not want, I want the fans coming on for the coolant in the engine, not after the radiator has cooled it down. They don't give you the option to control ECT1 for 9th gens because it controls the fans.

BTW, are you NA or boosted on your 9th gen? If you're NA, have you compared how accurate the wideband is to the stock o2 sensor in WOT operation? I am curious how close a 9th gen is, I've determined through a few customers that the 8th gen has a variance of about .2 on the fueling in the midrange and almost dead on accurate up top. I've never had a 9th gen with the wideband wired in, but I am curious to see how accurate the stock sensor is to your wideband reading on wide open throttle.
Burban1880
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Location: Ohio

Re: ECT2 & ELD question

Post by Burban1880 »

I totally agree with you about the ECT sensors and how Flashpro manages them. That's why it didn't make sense to use the ECT2 for the wideband if it were to potentially make the fans inoperable. I will say unless it labeled different in my Flashpro manager, it seems like the fans get its info from the ECT2 sensor and not the ECT1. When I have the car running and I'm looking at the data. When the fans turn on at set parameter of 194*F, ECT1 is anywhere between 205-215*F and ECT2 will be 194*F according to Flashpro. It doesn't seem like the function of the fan settings correlate with the readings from ECT1. Trust me it makes no sense.

I am boosted and I will say at WOT the stock o2 sensor reads richer than the wideband by 1-2 units. Stock will report 10a/f while the wideband will show 12a/f. For part throttle driving the two almost emulates each other but as soon as the a/f gets around 12.5-12.8 on the wideband the stock sensor starts to read rich.
Flashpro will not give me a stock corrected a/f reading for some reason.
EFICU
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Re: ECT2 & ELD question

Post by EFICU »

Yeah it looks like you might be right on the fan operation using ECT2 according to some forums posts. Just doesn't make any sense, which then makes your point of what happens if you disable the second ECT in FlashPro. Of course, perhaps disabling it in the FlashPro might just disable the reading to record in the datalog. I have a datalog from a guy who had the second ECT disabled in the tune by unchecking that box, in summer of Texas his car gets up to 198* at idle and then cools down to 194 within about 30 seconds in the datalog. Interesting I guess, it almost seems like unchecking that is similar to an 8th gen where it causes the ECT1 to become the fan controller based on this datalog. I think you still made the right choice going the ELD route.

Interesting on the AFR comparison. I am anxious to get a 9th gen who has the wideband wired in so I can find out how close they are. I would imagine it's a similar reading even though you're boosted, but I would want to see an NA car just to compare for the bulk of work I do. I was glad to have a handful of 8th gens now that I studied the readings to gauge how close. The AF corrected is very close on those, which AF corrected isn't available on 9th gens. They made it for 8th gen ECU family so anything 8th gen related like FN2s, CSX, and even S2000 it is available for some reason. Though on S2000 the reading is very different and the forums have a very different opinion on which reading is correct. That's sort of why I am anxious to get some 9th gen data from a wideband to compare.

Sorry for gumming up your thread about the ECT2, I should have left it alone for the Hondata boys to answer. Hopefully I didn't screw you up too bad, and thanks for the data on the wideband.
Burban1880
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Joined: Tue Nov 10, 2020 8:36 pm
Location: Ohio

Re: ECT2 & ELD question

Post by Burban1880 »

Oh don't worry you were not gumming up the thread about the ECT2. I just wasn't sure and thought maybe you knew something i didn't, no worries.
It doesn't make any sense as to why they would disable any operation of those inputs especially if its detrimental to a function of the engine.

I will say though there seems to be small latency with the wideband data when you look at the data log compared to the stock o2. I kind of expect that knowing how the signal is processed.

I do have a/f corrected but it shows the same values as the a/f reading from the stock o2 sensor; the is no correction between the two. I don't know if I'm doing something wrong or there is no correction for the 9th gens.
Thank you for the help.
EFICU
Posts: 3295
Joined: Mon Feb 25, 2019 10:14 pm

Re: ECT2 & ELD question

Post by EFICU »

Okay good, I didn't want you to miss out on information you were looking for.

Yeah the AF corrected will show up on any car I believe, but the correction factor only works for 8th gen Si platforms, and S2000s, in my experience. Spunkster talks about it here in the post viewtopic.php?t=20507 . It's basically in the channels, but doesn't actually have a function except for 8th gen Si types, like the Euro FN2, Acura CSX in Canada, etc. For the S2000 it's in there, but the reading is very different and Hondata says don't use it really for anything other than 8th gen Si types, FN2, CSX. The reading will be the same for AF and AF corrected on your ECU type.
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