Ethanol Sensor Spikes, high 1.30 kctrl, Coolant Gauge Disappearing, and Diagnosis/Fix!

Static_Awesome

IG:Static.Awesome
Joined
Jun 22, 2019
Threads
8
Messages
121
Reaction score
103
Location
Florida
Vehicle(s)
2019 Civic Si Coupe
Country flag
Evening all! I recently installed the PRL Flex Fuel Kit (amazing hardware btw!), flashed the TSP Stage 2 Tune, and was doing some shakedown pulls. Prior to this, I noticed ethanol percentage would go from 9/10% on 93, which is normal and expected. Occasionally, I would notice it reporting 15+20% intermittently, and couldn't find any info, so assumed it was normal.

Spoiler alert, it definitely is not normal for it to jump a lot on the same fuel.

Everything looking "Okay", I slowly increased pedal and boost and went to Map 2, and then Map 3. Fuel trims looked amazing, car felt okay despite what I assumed were normal ethanol readings.

Everything was fine until it wasn't. KCtrl shot up, fuel trims looked fucky, and my coolant temp gauge (ECT1 and gauge cluster) went to zero and then back up. Ethanol reported anywhere from 0 to 98%. No codes occurred, probably because this was a shakedown test and I didn't let it ride that way long.

Me and my backup driver parked it, and thought it was a bad install by us. It absolutely was, the ground for the kit was loose. After tightening, everything was fine, KCtrl started dropping, ethanol readings were solid 9/10%. Reflashed, KCtrl dropped from .59 default to "best" learned .49. Posting this so if anyone else has a similar issue, hopefully they find this thread, and pinging @PRL Motorsports , @KTuner , and @Two Step Performance so they can best help through customer support if they haven't seen these symptoms/fix before. Stay safe all!
Sponsored

 
OP
OP
Static_Awesome

Static_Awesome

IG:Static.Awesome
Joined
Jun 22, 2019
Threads
8
Messages
121
Reaction score
103
Location
Florida
Vehicle(s)
2019 Civic Si Coupe
Country flag
Good job on the quick troubleshooting :thumbsup:

A bad ground connection is a common problem when installing aftermarket electronics like HID kits and amps and such.
I found it in less than 10 minutes, but as a computer expert, robotics hobbyist, and former satellite and radio technician, I should have figured it out sooner. Low or no readings are common with signal or power issues, or connections. High AND low is definitely a signal or power ground issue. Live and learn!
 

redcivic19x

Senior Member
First Name
Josh
Joined
Oct 20, 2019
Threads
22
Messages
336
Reaction score
225
Location
FL
Vehicle(s)
2019 Honda Civic SI Sedan
Country flag
I found it in less than 10 minutes, but as a computer expert, robotics hobbyist, and former satellite and radio technician, I should have figured it out sooner. Low or no readings are common with signal or power issues, or connections. High AND low is definitely a signal or power ground issue. Live and learn!
This is good info to know. I’m about to install the flex fuel kit in the coming weeks (just been sitting in my garage for the past 2 weeks). I just have to run mine with my oil catch can which is gonna require drilling in to the firewall and putting some rivet nuts in there
 

KTuner

Elite Sponsor
First Name
J.R.
Joined
Jul 10, 2017
Threads
30
Messages
2,792
Reaction score
3,423
Location
Chandler, Arizona
Website
www.KTuner.com
Vehicle(s)
2017 Si
Country flag
I was going to suggest grounding, but looks like you have that covered. Great to share the experience for others who may run into issues. Thank you.
 


OP
OP
Static_Awesome

Static_Awesome

IG:Static.Awesome
Joined
Jun 22, 2019
Threads
8
Messages
121
Reaction score
103
Location
Florida
Vehicle(s)
2019 Civic Si Coupe
Country flag
I was going to suggest grounding, but looks like you have that covered. Great to share the experience for others who may run into issues. Thank you.
My thinking about the KCtrl values and ECT1/Gauge disappearing was that although KTuner repurposes ECT2, it doesn't change the factory error states for when that sensor goes dead or out of range. Does that line up with y'all's experience? I can't explain how else the gauge would be affected.
 
OP
OP
Static_Awesome

Static_Awesome

IG:Static.Awesome
Joined
Jun 22, 2019
Threads
8
Messages
121
Reaction score
103
Location
Florida
Vehicle(s)
2019 Civic Si Coupe
Country flag
Gauge shouldn't be affected. You disabled ECT2 to use Flex and the gauge doesn't rely on ECT2 anyway.

No suggestions.
That's... Disconcerting. Might be an unknown feature of the stock ECU, failsafe rereading of ECT1 if ECT2 gets out of whack? Definitely didn't physically touch ECT1 since it's on the opposite side, but it definitely went to minimum and then back up, on the gauge and ECT1 reading in KTuner. I'm pretty sure I have logs if y'all are interested.
 
OP
OP
Static_Awesome

Static_Awesome

IG:Static.Awesome
Joined
Jun 22, 2019
Threads
8
Messages
121
Reaction score
103
Location
Florida
Vehicle(s)
2019 Civic Si Coupe
Country flag
Gauge shouldn't be affected. You disabled ECT2 to use Flex and the gauge doesn't rely on ECT2 anyway.

No suggestions.
And to confirm what I saw, here's the log of what happened. KCtrl shot up to 1.30 despite no knocks, ECT1 spiking up and down.

Honda Civic 10th gen Ethanol Sensor Spikes, high 1.30 kctrl, Coolant Gauge Disappearing, and Diagnosis/Fix! Capture.PNG
 

Attachments

KTuner

Elite Sponsor
First Name
J.R.
Joined
Jul 10, 2017
Threads
30
Messages
2,792
Reaction score
3,423
Location
Chandler, Arizona
Website
www.KTuner.com
Vehicle(s)
2017 Si
Country flag
You disabled ECT2 to use it for flex. It's no longer used in factory capacity.

If ECT 1 was affected that's likely due to your wiring issue, which you solved. Not sure what more needs focused on there.
 
OP
OP
Static_Awesome

Static_Awesome

IG:Static.Awesome
Joined
Jun 22, 2019
Threads
8
Messages
121
Reaction score
103
Location
Florida
Vehicle(s)
2019 Civic Si Coupe
Country flag
You disabled ECT2 to use it for flex. It's no longer used in factory capacity.

If ECT 1 was affected that's likely due to your wiring issue, which you solved. Not sure what more needs focused on there.
You're the experts, and I definitely defer to that. Thanks for confirming, you guys really are the best!
Sponsored

 


 


Top