Idle Tuning

[D.A.V.E.]

So, I just got a new tune from a member who has a similar setup to mine and have a few questions for you guys out there

My Setup:
JSRC-r 4" Pulley
Hondata IMG
Fujita CAI (RSX-s)
denso ik24 spark plugs
RSX-s valve springs
Comptech Shorty Header
Megan test pipe
JP Performance mid-pipe
stock axle-back

I was running the stock JRSC-r tune with some street tuning by JPAX. Call this "stock". Everything was ok except I was only getting 22-24 mpg. This new tune got me 28 mpg on my first tank of mixed driving. :cheer2:

The only problem I'm having is at idle. It seems to be idling very rough and when I let the rpms drop from high, the rpms dip low. 950 idle set, can dip as low as ~500. My idle was pretty good with the stock tune.

So here are the differences between the 2 tunes:
- Force Radiator Fan on (Stock 212, New 204)
- Idle Duty Cycle (Stock Middle, New Little to right)
- Overall fuel trim (Stock 0, New 5)
- Cranking fuel trim (Stock 0, New -5)
- Disable O2 Sensor heater/response (Stock no, new disabled)

Also, in the "Low speed cam" the new map has much less fuel and much more VTC advance.

I'm going to start playing with the Idle duty cycle, but what else can I safely do to make the idle better? Why would the O2 sensor things be disabled?

[dustyboner]

i revised the NEW.kal . upload it to your k-pro and then follow these steps to get your idle where you want it.

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1. Make sure your TPS is set so that it is between -1 and 0 at idle.
PARAMATERS\(knock/TPS)\scale TPS.
2. Datalog and check that the cam angle is zero at idle. If not, check #1
3. Alter the idle valve duty cycle adjust slider value. Rev the engine to about 3000 rpm and release the throttle quickly. If the rpm drops below the idle speed and then recovers, then move the slider to the right. If the rpm drops to 500 above idle speed and then goes slowly down to idle speed, move the slider to the left. See below about how this is affected by the ECU idle learn.

Note that after uploading a calibration the ECU takes a little while to learn the correct duty cycle for the idle valve (even if the upload is a very small change it resets the ECU's memory). If the car is hot then this learning process happens in a couple of minutes, but if the car is cold the ECU won't learn until the car is hot - and in the meantime, the engine sometimes stalls with large injectors. The trick is to not increase the idle speed too much to prevent the engine stalling if the engine is cold, because it will fix itself once the ECU learns the idle.

If you get a slight misfire at idle once the car is warm, slowly enrichen the idle target A/F ratio.
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[D.A.V.E.]

So I don't have to dig around the file a bunch. What did you change?

[4angrybadgers]

Your IAC valve may be sticking as well.

[talonXracer]

REMEMBER that when you adjust the idle slider in Kpro you need to complete a idle relearn before it takes affect.

[D.A.V.E.]

Your IAC valve may be sticking as well.

Thanks for the input, however my other tune idles just fine. That rules out a sticky IAC valve.

I'm gonna try just messing with the idle slider. I was messing with it before but I never did the re-learn between adjustments.

[SyckSiR]

i revised the NEW.kal . upload it to your k-pro and then follow these steps to get your idle where you want it.

----------------------------------------

1. Make sure your TPS is set so that it is between -1 and 0 at idle.
PARAMATERS\(knock/TPS)\scale TPS.
2. Datalog and check that the cam angle is zero at idle. If not, check #1
3. Alter the idle valve duty cycle adjust slider value. Rev the engine to about 3000 rpm and release the throttle quickly. If the rpm drops below the idle speed and then recovers, then move the slider to the right. If the rpm drops to 500 above idle speed and then goes slowly down to idle speed, move the slider to the left. See below about how this is affected by the ECU idle learn.

Note that after uploading a calibration the ECU takes a little while to learn the correct duty cycle for the idle valve (even if the upload is a very small change it resets the ECU's memory). If the car is hot then this learning process happens in a couple of minutes, but if the car is cold the ECU won't learn until the car is hot - and in the meantime, the engine sometimes stalls with large injectors. The trick is to not increase the idle speed too much to prevent the engine stalling if the engine is cold, because it will fix itself once the ECU learns the idle.

If you get a slight misfire at idle once the car is warm, slowly enrichen the idle target A/F ratio.
______________________

cam angle is never always gonna be at zero....sometimes it is and sometimes its not...theres not a whole lot u can do about it.....at times my cam angle runs from 1-12 at idle and sometimes stays at zero....

[D.A.V.E.]

Any comment on disabling the o2 heater/sensor??

Hondata has it enabled, this new tune doesn't?

[dustyboner]

Any comment on disabling the o2 heater/sensor??

Hondata has it enabled, this new tune doesn't?

http://i198.photobucket.com/albums/aa147/dustyboner/647de520.jpg

[dustyboner]

cam angle is never always gonna be at zero....sometimes it is and sometimes its not...theres not a whole lot u can do about it.....at times my cam angle runs from 1-12 at idle and sometimes stays at zero....

mine always is at zero. look at this .kdl if ya have any doubts