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Old 01-18-2010, 05:15 PM   #1
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Default Really high idle

After changing to the new water temp calibration, I retuned my idle settings and calibrated my tps today. After a short drive, in the middle of the drive it stopped cutting fuel during deceleration and the idle rpms shot up to 2500-3000 rpms. I checked for leaks with brake cleaner and didn't find anything. I tried my old map and the idle was still high. I also checked to see if the throttle was stuck open and it wasn't.

I am including the log of the run and map. If there is anything you see that stands out please let me know. I'm not sure yet how to read it to make sure everything is working properly.
Attached Files
File Type: zip NB8A_600cc_3Bar2 correc trans water.zip (2.0 KB, 48 views)
File Type: zip 1-18-2010_1324.zip (185.5 KB, 60 views)
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Old 01-18-2010, 06:25 PM   #2
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One thing I noticed about this log over others with no idle issue is that the idle position is reading a lot lower than supposed too (10-14). In the settings based on water temperature it is supposed to be reading around 60. Can anyone help me on this?
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Old 01-18-2010, 07:37 PM   #3
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I haven't had any issues with the new water temp calibration #'s. Your high and low coolant enrichment maps look way different than mine. Throttle off over-run min temp is set to 127c which you may never reach. You might want to change your overboost protection as needed. I was told it's safest to cut both ignition and fuel.
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Old 01-18-2010, 11:39 PM   #4
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Thanks for checking sv650,
The throttle off and overboost protection settings were in the base map and I haven't gotten around to changing them until now. I lowered the temperature to 115c, but I'm not sure what throttle off over-run is meant for. I also lowered the overboost protection from 250 to 190. I haven't calibrated the map yet.

Without changing or fixing anything the idle all of a sudden is back to normal.
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Old 01-19-2010, 12:56 AM   #5
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Over-run cuts fuel when you're completely off the throttle (coasting, but still in gear, like downhill or slowing for a stop light). It's to help fuel economy, the stock ECU does this...

I just enabled mine today.

RPM lower = 1400
RPM upper = 1500
Min water temp = 60*
Time delay (changed mine to 250ms)
Only when in gear (checked)
Not when A/C on (un-checked) <- I'll see how this works in 6 months when it gets warm again...

Works great. I don't feel a difference at all, but AFR goes full lean on throttle off now. Might as well save some gas...
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Old 01-19-2010, 04:59 AM   #6
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Check your open loop warmup idle settings too.
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Old 01-19-2010, 10:35 AM   #7
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fyi - i think these originally came from y8s

Name:  coolantenrichhi.jpg
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Name:  coolantenrichlow.jpg
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Name:  airtempigntrim.jpg
Views: 4
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Name:  airtempenrich.jpg
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Name:  airtempcorrection.jpg
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Size:  42.2 KB
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Old 01-19-2010, 04:39 PM   #8
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I had the same problem after working with a fellow member here on my car. Idle was great most of the time but then would out of the blue shoot to 4k...

anyhow, I flashed the FW once more and the problem went away...

Now I just have to figure out why my car idles with 60-80kpa of load now... no leaks; but at idle she pulls a hella lot of load. If I decel, the vacuum goes to normal... so I gotta figure this out...

Cheers,
Matt
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Old 01-19-2010, 08:03 PM   #9
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Quote:
Originally Posted by Prospero View Post
Now I just have to figure out why my car idles with 60-80kpa of load now... no leaks; but at idle she pulls a hella lot of load. If I decel, the vacuum goes to normal... so I gotta figure this out...

Cheers,
Matt
Today I had a whole new issue where my idle started to hunt badly at start up and is now reading 43kpa at idle when before it was around 33. It through off my whole fuel map and transient throttle settings. Right now I'm retuning the idle settings but can't get it to idle like before in closed loop.

Thanks SV650,
I don't want to use anyone else's settings yet since changing one setting makes me have to back track and fix everything I've done to get the car running.
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Old 01-20-2010, 10:34 AM   #10
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Are you road tuning your car?
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Old 01-20-2010, 06:15 PM   #11
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Quote:
Originally Posted by dgmorr View Post
Are you road tuning your car?
Rapid learn or tuning while driving? I have been tuning based based on logs as of now.
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Old 01-20-2010, 06:25 PM   #12
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Quote:
Originally Posted by sv650_ck View Post
fyi - i think these originally came from y8s



Aren't the high settings supposed to be +10 of the low settings?

Last edited by PhantomRoadster; 01-20-2010 at 09:41 PM.
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Old 01-20-2010, 06:38 PM   #13
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Quote:
Originally Posted by Prospero View Post
I had the same problem after working with a fellow member here on my car. Idle was great most of the time but then would out of the blue shoot to 4k...

anyhow, I flashed the FW once more and the problem went away...

Now I just have to figure out why my car idles with 60-80kpa of load now... no leaks; but at idle she pulls a hella lot of load. If I decel, the vacuum goes to normal... so I gotta figure this out...

Cheers,
Matt
Prospero,

Upload a log please!
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Old 01-20-2010, 08:28 PM   #14
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OK I looked this over...

dont worry about the throttle off overrun. setting it to 127 just turns it off.

What's weird on your logs is that your idle is always 10-14 when driving or otherwise. It doesn't appear to be doing anything at all.

Another thing I notice is the Aux Out is set to 1kHz and should be 500Hz. 1k might be too fast for the valve.

So with that datalog showing your idle value stuck at 10, I have to wonder if the idle screw is open too far. That means the idle controller is constantly trying to close down the valve and hangs out at the minimum value all the time.

Here's a way to try and set it properly:

1. Warm up the car completely.
2. Set your P, I, and D to zero so you're in open loop. (your car might rev high depending on the open loop effort settings... you may want to set all those around 90+/- to "10" to help).
3. Set your Overall Control Max and Min to 1 and 2 respectively. This will close the valve all the way down.
4. Grab your favorite Philips screwdriver and start closing the idle screw (righty tighty) until the RPM is around 700-750.

Then go back into the map and set your PID back to 2, 5, 3 and max and min control to 10 and 85. (The valve is essentially always open at 85% DC)

See if that works.
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Old 01-20-2010, 09:40 PM   #15
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Thanks for looking through it, but as I mentioned later on that day the idle went back to normal without me changing anything at all. Not sure why. My idle settings are around 60. When I set PID to 0, nothing usually changes at all. I figure the throttle is at the appropriate position. Not sure what happened that day.
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Old 01-21-2010, 12:03 PM   #16
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I bet it was colder out, and with the air density being slightly higher, the IAC valve was basically full closed but the bypass was still letting too much air in.
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Old 01-21-2010, 12:33 PM   #17
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phantom,
you should still try to fix your open loop idle efforts. the system uses those before settling into closed loop I believe.
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Old 01-21-2010, 07:31 PM   #18
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Sorry to come back to the party so late.. work has been a bitch...

Here is a log from just the other day. Y8S found a few issues with my rapid learn setting to kick in at 700 RPM but even with a fresh, un-touched map... I still have really high loads at idle for some reason.

Here is the log, and I hope to go out and mess with the car on Sunday... but first I am painting a Corolla for my GF.. lol...

1-17-2010_1733.zip

BTW, Y8S... thanks again for the help and your keen eye is killer. I missed that 700 RPM thingine Car is great outside of this really rich idle and it pulling almost 70+ kpa... dunno wtf that is about yet.

Cheers yall!
Matt
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Old 01-21-2010, 11:29 PM   #19
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come over this weekend. we'll calibrate your map sensor properly and if the kPa is still high at idle, I'l find it.
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Old 01-22-2010, 02:32 AM   #20
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Prospero,

Your car is running +50 vvt advance, that's the reason for high load at idle. Unplug the vvt connector on the valve cover.

Check my "Have I screwed up my ocv valve" thread.
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