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Discussion Starter #1
K-Tuner doesn't offer any tuning support, or real explanations of the values in the maps, etc. I posted the following in their forum, and the reply was "we don't offer tuning advice"

Anyone on here have any insight on tweaking these settings?

'05 PND ECU, K24/K20 IHE base code

I'm driving the car when I can to get everything settled. Runs very well once up to operating temp. The problem is that during warm up throttle tip-in & part throttle response is very jerky.

I'm trying to figure out which parameters it would behoove me to adjust to resolve the warm up drivability.

Fuel cut? TPS value = % of throttle angle



ECT ign? (in degrees)


ECT fuel? (%)


SInce my issues seems primarily to revolve around low load / lower rpm trailing and tip in (driving on local streets, on/off the throttle in small degrees)

I'm thinking I should look at the fuel cut first.



The preset values are based on a 'normal' idle baseline? I'm trying to judge what would make sense in terms of adjustment. My idle is around 1050-1100. With the 80mm K-Tuned TB, I just can't seem to get it lower than that.

So, the question is, should all 4 tables in the first column be adjusted equally/proportionately?

I can understand the MAP based cut & recover have a 400-350 rpm window, so I assume that needs to be maintained when raising the minimum.

Should I just revise the TPS vs Min RPM & Fuel Cut Delay? Start with about 1000rpm over base idle?

I'm puzzled that the Max Throttle for Cut value = 5(%) - when the TPS vs Min RPM values are 3.3 & 8 (?)

Fuel TipIn: he said this is raw fuel values, for what that is worth.



Thanks for any input
 

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Disclaimer: I have no experience using K-tuner. That said I work with engine calibrations for a living. I could be wrong but the "Fuel Cut" screen grabs APPEAR to be deceleration fuel cut settings to me just looking at the engine speed ranges, TPS ranges and the MAP values. If that's the case I wouldn't think they'll help your transient throttle problems.

Is there any way to data log on a K-tuner? It'd be interesting to see what spark and lambda are doing during steady operation into a cold tip-in compared to hot tip-in.

Can you also tell us what ECT ranges you see for this "cold" condition and at what ECT it seems to go away?
 

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Discussion Starter #3
Disclaimer: I have no experience using K-tuner. That said I work with engine calibrations for a living. I could be wrong but the "Fuel Cut" screen grabs APPEAR to be deceleration fuel cut settings to me just looking at the engine speed ranges, TPS ranges and the MAP values. If that's the case I wouldn't think they'll help your transient throttle problems.

Is there any way to data log on a K-tuner? It'd be interesting to see what spark and lambda are doing during steady operation into a cold tip-in compared to hot tip-in.

Can you also tell us what ECT ranges you see for this "cold" condition and at what ECT it seems to go away?
Thanks for responding.

They told me the fuel cut settings can impact the on/off/trailing throttle jerkiness that happens when the target idle is much higher than stock - in my case base idle target is around 1050-1075 instead of around 850. They said I may need to raise the rpm or lower the TP % in the Fuel Cut settings - the symptom is that if I'm basically trailing throttle or barely touching it, the engine will suddenly pull back, feels like when the fuel is cut.

That symptom is aggravated during warmup, so 50-160ºF range - once normal op (190 -210ºF) is achieved, that symptom only occurs once in awhile, not every time I get on/off the throttle

I can log, the problem is I can only view the log in realtime, no way to play at half speed over what may be a trouble area, for example. Recording a 3-5min segment & playing it back to find the jerky area is difficult since I don't know what baseline to follow to look for deviations that would indicate the problematic area. I can export the log as CSV file.
 

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It looks like there's a TPS based fuel cut as well as a MAP based fuel cut, the MAP based is far more complex. Without the logic it's hard to know which one takes precedence at any given operating condition, but you could "calibrate out" the TPS based by pushing the rpm values up to something unreasonable like 9000 and see what happens. You describe the issue changing with engine temperature though, so my suspicion is if the problem is coming from the fuel cut logic it's likely more related to the MAP based fuel cut.

What is the reason for targeting an elevated idle? Are you running aftermarket cams? I always trouble shoot by looking at the three inputs, fuel, air and spark.
1) If the engine runs a consistent lambda = 1 when it's warm, this probably isn't the problem.
2) I don't know how Honda handles it, but if you're running standard idle speed control settings for spark I'd hesitate to say there's a problem. I tried installing the software but you need a device to actually get into it. I'm imagining they have something simple that retards spark to reduce engine speed and advances it to speed up.
3) Air has a lot of variables, first i'd be curious to know what cams you've got, what MAP you read during a hot idle, and what your intake camshaft advance schedule looks like. It could also be related to manifold leaks or the 80mm throttle you've got. If there's a leak, the MAP based fuel cut windows could be too low to work properly, in which case shifting the mBar values up wouldn't be unreasonable, but without an idea of what kind of MAP you reach with a closed throttle it's hard to say.
 

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Arouse the DAMPFHAMMER!
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I can log, the problem is I can only view the log in realtime, no way to play at half speed over what may be a trouble area, for example. Recording a 3-5min segment & playing it back to find the jerky area is difficult since I don't know what baseline to follow to look for deviations that would indicate the problematic area. I can export the log as CSV file.
I would appreciate a log file to see it better. Normally such a behaviour is sourced in a mismatch of fuel and air and the TB corresponding torque demand. If it happens only at a certain operation condition, it is likely based on not ideally fitting correction of fuel. But also a non hysteresis closed loop switch issue can cause this around the deceleration cut off. But like Scider said, without any log it is difficult to understand precisely.
 

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Discussion Starter #6
Thank you so much for your input - everything helps in terms of my understanding of where & what to look for.

I'll log a warm up / driving session and export as CSV.

The K-Tuner doesn't allow anyone who hasn't purchased to see what's in there, which sucks since they also offer ZERO tuning tips in the software. The HELP is much help (to me) either. I've used TunerPro on my old Volvo, and at least with that, if you hovered over a parameter it would give you tips as to making adjustments


To answer some immediate questions -
I have stock K24a2 '06 cams ('05 motor).
Lambda is consistent when warm.
There are parameters for target idle ign
I have the 80mm TB - no vacuum leaks since I repaired a faulty weld in the plenum. I smoke tested it. When I blocked off the IACV ports, it will idle at under 800 rpm, but with IACV regulating, I get surging if idle targets are set to normal levels - this is an older map - I raised the warm idle target to 1075 & the surging (and occasinal P0511 code) went away.

 

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Discussion Starter #7
I drove the car to work yesterday morning - 15-20min drive, mix of local & highway driving so perfect for a comprehensive driving log. It did pour with rain in the north of the county where my school is, so I was able to check that I am leak free around the doors and targa .

What I noticed while driving (I glanced at the main screen to make sure the recording was staying active) that displayed throttle % was not matching my pedal position in that low tip-in range - it seemed to be lagging behind the actual. Anyway, I completed the logs, did what I needed to do at school, and went home to get on with the iLearning school day. As an aside, when I left school I noted that the battery voltage was low & cranked a little slow. I realized the battery is probably 7 years old now.

After work, I went & bought a new Interstate M-24F in town, and I decided before I sent in the datalogs for review, I'd better check the TPS setting relative to butterfly opening/pedal position, so I hooked up the laptop & checked it from the pedal, and from the bobbin. In both cases there was a lag - in other words, the throttle plate was open several degrees before it registered. It seemed to me that that would explain most if not all the drivability issues. It was puzzling, as I had gone over the butterfly & TPS settings several times.

There is no way to get to the TPS without removing the TB





After removing the TB, I had to remove the TPS & K-Tuned adaptor plate & rework the plate mount again - as an addtional complication, the way K-Tuned mounted this (below) the TPS was not in the proper range. The new problem was that in the modified position, I had not allowed for a wide enough adjustment window, and it was all the way up against the stop. I had to dremel the slot to allow the mount plate to rotate another few degrees CCW, which then moved the TPS mount screws into the middle of the adjustment range. With that, I was able to center the TPS on the shaft, and get it adjusted so that the butterfly angle registered in the software immediately, with no lag or disconnect.

(Old pics, to illustrate TPS mounting)




Put it back together, double checked the butterfly response from the bobbin & at the pedal, all good. I took it for a drive to check if that resolved the problem, which it certainly seemed to have done.

I did a log after all that also - unfortunately I crashed the car on the test drive. Hit some debris on an entrance ramp bend & had to choose between grass embankment or a guardrail. Still went over a metal base & ripped the oil pan & nose damaged when I hit the embankment. Shut it down the moment I stopped, so maybe 15-30 sec. It's gonna be awhile before it's back on the road.







also bent the custom subframe


where the front swaybar used to be attached, and floor pan pushed in...

 

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Arouse the DAMPFHAMMER!
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...the throttle plate was open several degrees before it registered.
Nice find HusseinHolland! This correlates directly into fueling between idle and nomal operation mode of the ECU.

As a side note to K-Tuned: all products I ever bought from K-Tuned were of low quality or out of spec and had to be reworked. I am not sure if this my high quality expectation or just the K-Tuned product quality was shipping. E.g. the water pump delete plate had machining scrates, the O-ring nut was wrongly designed for the supplied O-Ring and the water inlet bore ID was way to small to feed a race engine. Just one example of the engineering capability of K-Tuned, which let miss basic rules of engineering and quality measures.

...I did a log after all that also - unfortunately I crashed the car on the test drive.
Oooouuuuuuhhhh, I am really sorry for your crashed car and your effort you will now have to bring it back to it's glance. Are you going to repair it?
 

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Discussion Starter #11
Oooouuuuuuhhhh, I am really sorry for your crashed car and your effort you will now have to bring it back to it's glance. Are you going to repair it?
Yes, It will be restored to it's former beauty :D Just means I won't be enjoying driving it this year, or taking it to the various car shows I had planned.

I probably won't do the paint this time - I don't feel capable of blending into the rest of the paintwork. It was one thing shooting the whole car, however this will be beyond me. So, I'll do the bodywork & then talk to a shop I know for the paintwork.
 

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Arouse the DAMPFHAMMER!
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Yes, It will be restored to it's former beauty :D Just means I won't be enjoying driving it this year, or taking it to the various car shows I had planned.
That's great! I am looking forward to see it comming back. Regarding the less joyment, my 2 Liter engine's gearbox broke at the dyno. It pushed 274 [email protected] rpm on to the roll, that are 101 ftlb/liter! I was almost there, proving a 4000 rpm bandwidth of 96 ftlb/liter with an NA engine is possible. But the gearbox stopped my journey hard. I understand your loss, and I know, the next time it will be even better! Good luck for your restart of your project.
 

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Discussion Starter #13
Finally have the car together enough to drive it (not completed, just to make sure engine wasn't damaged) - I found that the tip-in jerkiness is back. I don't know if it;s the KTuned TB or the TPS that is flaky. Certainly the adjustment shouldn't change all by itself.

The other question I have is related to coolant temp -I'm curious what others in mid-engine setups find their normal opertaing temp to be. I have the 180ºF range t/stat in there, however the coolant temp is typically right around 200ºF in normal use.







 

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Arouse the DAMPFHAMMER!
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Finally have the car together enough to drive it (not completed, just to make sure engine wasn't damaged) - I found that the tip-in jerkiness is back. I don't know if it;s the KTuned TB or the TPS that is flaky. Certainly the adjustment shouldn't change all by itself.
Wow, what a decent progress and look!

The other question I have is related to coolant temp -I'm curious what others in mid-engine setups find their normal opertaing temp to be. I have the 180ºF range t/stat in there, however the coolant temp is typically right around 200ºF in normal use.
On my previous stock K20A2 setup I had around 186-190 °F while cruising around in the mountains on a 90 °F day. I've run hill climbs races with it, which is really a challenging application for the cooling system (low VSS + high output of heat power = 🥵) where the coolant temp reached 198 °F. With my DAMPFHAMMER setup, everything changed and I have even on the dyno with an 40,000 m³/h fan just 190 °F under continuous WOT conditions.

Just in case if under continued WOT condition the coolant temperature even more increases I would suggest following:
  1. increase the cooling area of the radiator or improve its efficiency (better use of the radiator area, and so on)
  2. check the water pump flow and improve that if necessary
Why? Normally at around between 198 and 201 °F the fan gets activated. The fan is an emergency part of the cooling system to keep the engine cool under lower speed (traffic jam). Under normal operation the engine should never get into that area, because the fan makes just 10-20 m/s air velocity before the radiator. If VSS is above that, the fan makes no sense, it just decelerate the air flow through the radiator. Your feeling is pretty right, there is something not working properly.
 

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When I redesigned the fan system for my E39 M5 using a SPAL fan and a PWM variable speed controller from Derale. I had a lot of troubles until I came to a few somewhat controversial conclusions.

1) Thermostats are used to heat an engine up.
2) Airflow/fans are used to cool an engine down.

At a steady state cruise, you might run into an equilibrium situation where you have enough airflow through the radiator and coolant flow through the engine to allow the thermostat to control to 180 degrees, but I've found that most of the time the engine temperature is just above the thermostat opening temperature and the fans are doing the cooling work. It's critical to have the fan activation temperatures above that of the thermostat, otherwise they wont operate correctly because there's no coolant flow through the radiator.

Are you using the standard Fiat 1/9 radiator? I've actually recently been doing a lot of research on radiators for my Exocet build, and the 1/9 was one that I thought about because of it's profile. I'm also looking to do an angled radiator installation, so radiator height is a concern.
 

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Discussion Starter #16
When I redesigned the fan system for my E39 M5 using a SPAL fan and a PWM variable speed controller from Derale. I had a lot of troubles until I came to a few somewhat controversial conclusions.

1) Thermostats are used to heat an engine up.
2) Airflow/fans are used to cool an engine down.

At a steady state cruise, you might run into an equilibrium situation where you have enough airflow through the radiator and coolant flow through the engine to allow the thermostat to control to 180 degrees, but I've found that most of the time the engine temperature is just above the thermostat opening temperature and the fans are doing the cooling work. It's critical to have the fan activation temperatures above that of the thermostat, otherwise they wont operate correctly because there's no coolant flow through the radiator.

Are you using the standard Fiat 1/9 radiator? I've actually recently been doing a lot of research on radiators for my Exocet build, and the 1/9 was one that I thought about because of it's profile. I'm also looking to do an angled radiator installation, so radiator height is a concern.
Thank you both for your replies.

I had a custom rad built that is larger (taller & deeper) core and end tanks by Howe Racing. I made a drawing & they built it according to my spec





Based on your and LE's responses, what I need to investigate / add is a better fan management system. I'm not using the (EMS) built in ground trigger - I'm relying on the Fiat thermoswitch. Since the engine temps typically run at least 15-20ºF higher than the coolant temp in the rad, I need to switch fan control to the engine temp. I will investigate ways to use the ground trigger.

For the throttle issue, I'm looking at getting a slightly smaller TB, with a different TPS since this setup clearly doesn't hold the physical setting I make for any length of time.
 

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Discussion Starter #17
72mm TB came - I chopped a section of an Accord manifold to revise the offset of the flange from where it is now - I need more space for the TPS access. Also I have to have the IACV on top not below, so I'll weld the flange upside down when I have it figured out

 

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Arouse the DAMPFHAMMER!
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...Since the engine temps typically run at least 15-20ºF higher than the coolant temp in the rad...
How does the temperature difference come? Temperature measurement for ECT happens around 70 mm before at Engine Coolant Outlet. The temperature may fall by 1.0 °F on the way down to the radiator at max.. Why should they be lower then that? Do we speak about a radiator inlet temperature? Or does your fan control system relay on the outlet temperature of the radiator? Please bring some light in here.
 

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Arouse the DAMPFHAMMER!
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72mm TB came - I chopped a section of an Accord manifold to revise the offset of the flange from where it is now - I need more space for the TPS access. Also I have to have the IACV on top not below, so I'll weld the flange upside down when I have it figured out...
I hope this work it out. If not, is KTuner able to control a DBW?
 

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Discussion Starter #20
How does the temperature difference come? Temperature measurement for ECT happens around 70 mm before at Engine Coolant Outlet. The temperature may fall by 1.0 °F on the way down to the radiator at max.. Why should they be lower then that? Do we speak about a radiator inlet temperature? Or does your fan control system relay on the outlet temperature of the radiator? Please bring some light in here.
The Fiat fan temp sensor is on the outlet of the radiator. I need to rewire the circuit to use the fan control built in to the EMS, so it is based on engine temp at the coolant outlet, not the temp about 3 metres away from the engine :D


I hope this work it out. If not, is KTuner able to control a DBW?
KTuner can do DBW, however I got rid of that TB, and I don't want to fit a DBW pedal assembly.. I'm also hoping this is more stable than the larger TB & TPS setup I have now.
 
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