Welcome to the North American Subaru Impreza Owners Club Sunday December 28, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Engine Management & Tuning

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 01-16-2010, 09:58 PM   #1
ohm
Scooby Specialist
 
Member#: 178468
Join Date: Apr 2008
Location: Somerset, NJ
Vehicle:
2007 UGM STI
IAG Built

Question Datalog - Knock Correction - Dirty MAF Sensor

Figured I would do some data logging today to check for anything strange. I noticed some negative values related to knock correction, and was wondering if this is shift knock or the knock sensor picking up false knock of some kind. I am hearing that negative KC values are acceptable in the lower RPMs, but at WOT it can be cause for concern.

I will add that the car is running great with no signs off any issues. I have an AEM wideband that reads 11.6 at WOT, and the car holds boost fine.

These logs were taken from 3rd-4th-5th gear. Any comments on the KC are welcome. Thanks.

Log 1
Code:
RPM	LOAD DAM	IADV	KC	TP	Boost	AFR	IDC	MAF	MAFV	VS
2638	0.8	1	33.5	0	36.06	-1.45	12.88	9.58	73.54	2.8	31.69
2755	1.76	1	18.5	0	99.96	1.89	15.07	17.33	83.46	2.74	32.31
2839	2	1	15	-1.4	99.96	3.48	12.19	19.91	97.11	2.96	32.93
2924	2.22	1	15.5	-1.4	99.96	5.37	11.5	19.64	112.13	3.14	32.93
3100	2.41	1	16	-1.4	99.96	7.83	12.88	23.4	124.64	3.26	33.55
3260	2.66	1	16.5	-1.05	99.96	10.88	12.88	27.59	152.89	3.48	36.04
3468	3.14	1	13	-2.45	99.96	15.95	11.15	40.5	189.88	3.84	36.04
3741	3.85	1	12	-2.45	99.96	22.19	11.15	54.8	270.44	4.18	39.15
4054	4.15	1	12.5	-2.45	99.96	22.19	11.15	60.61	281.31	4.26	39.15
4427	4.08	1	14.5	-2.1	99.96	22.19	11.15	62.72	292.42	4.3	44.12
4757	3.98	1	15.5	-2.1	99.96	22.19	11.15	67	317.05	4.4	49.09
5034	3.98	1	16.5	-2.1	99.96	22.19	11.15	71.87	347.06	4.48	49.09
5334	4.1	1	17.5	-1.75	99.96	22.19	11.15	74.77	350.22	4.56	55.92
5639	3.94	1	18	-1.75	99.96	22.19	11.15	76.49	370.05	4.64	55.92
5943	3.78	1	19	-1.75	99.96	22.19	11.15	77.91	379.67	4.6	61.52
6243	3.7	1	19.5	-1.75	99.96	22.19	11.15	80.28	377.74	4.6	67.73
6454	3.46	1	-12.5	0	32.93	14.94	11.15	58.44	208.34	3.74	67.73
5513	0.26	1	26.5	0	16.07	-8.41	11.27	8.15	36.75	2.3	72.7
4612	2.04	1	21.5	0	99.96	9.28	12.53	42.46	190.6	3.88	77.05
4910	3.92	1	18	0	99.96	22.19	11.15	76.09	353.4	4.54	77.05
5162	4.24	1	18.5	0	99.96	22.19	11.15	76.72	361.71	4.52	80.16
5300	4.12	1	19	0	99.96	22.19	11.15	76.15	357.23	4.58	80.16
5446	4.06	1	19.5	0	99.96	22.19	11.15	76.16	352.14	4.58	82.64
5644	3.96	1	19.5	0	99.96	22.19	11.15	77.17	366.2	4.56	85.75
5769	3.9	1	20	0	99.96	22.19	11.15	76.38	366.83	4.58	85.75
5896	3.83	1	20.5	0	99.96	22.19	11.15	77.29	377.74	4.6	90.1
6035	3.82	1	20.5	0	99.96	22.19	11.15	80.61	392.49	4.66	94.45
6180	3.74	1	21	0	99.96	22.19	11.15	79.17	380.31	4.62	94.45
6317	3.62	1	22	0	99.96	22.19	11.15	79.23	373.89	4.58	98.18
5947	1.73	1	-14.5	0	11.76	-5.08	11.15	29.94	57.09	2.18	98.18
5381	0.26	1	29	0	16.07	-9.14	11.15	8.01	33.85	2.3	101.9
5501	2.47	1	20	-1.4	99.96	13.49	11.85	63.71	294.76	4.32	103.15
5485	4.19	1	18	-1.4	99.96	22.19	11.15	83.81	393.75	4.64	103.15
5618	4.14	1	18.5	-1.4	99.96	22.19	11.15	80.55	384.8	4.68	105.63
5750	4	1	18.5	-1.4	99.96	22.19	11.15	79.93	374.53	4.64	105.63
5864	3.93	1	19	-1.05	99.96	22.19	11.15	78.62	367.48	4.6	106.25
5660	3.05	1	-12.5	0	13.33	0.29	11.15	29.77	86.94	2.94	109.98
5038	0.27	1	9	0	11.37	-9.72	11.15	6.32	18.8	1.82	109.98
4426	0.26	1	9	0	10.98	-10.59	11.39	5.73	21.64	1.8	111.23
4394	0.25	1	9	0	10.58	-11.02	12.19	5.64	16.72	1.74	112.47
4357	0.24	1	24	0	10.58	-11.31	11.96	5.56	18.8	1.76	112.47
Log 2
Code:
RPM	LOAD DAM	IADV	KC	TP	Boost	AFR	IDC	MAF	MAFV	VS
4079	4.09	1	14	-1.05	99.96	22.19	11.15	62.2	304.88	4.24	40.39
4465	4.02	1	15.5	-1.05	99.96	22.19	11.15	64.48	291.21	4.34	44.12
4765	3.91	1	17	-0.7	99.96	22.19	11.15	69.39	314.01	4.36	49.09
5072	4.02	1	17.5	-0.7	99.96	22.19	11.15	73.87	327.55	4.48	49.09
5438	3.88	1	18.5	-0.7	99.96	22.19	11.15	75.32	362.99	4.58	55.3
5758	3.83	1	19.5	-0.35	99.96	22.19	11.15	77.91	375.17	4.58	62.14
6030	3.77	1	20	-0.35	99.96	22.19	11.15	78.51	369.4	4.6	62.14
6299	3.64	1	21	-0.35	99.96	22.19	11.15	78.1	382.88	4.66	67.73
6520	3.55	1	22	-0.35	99.96	22.19	11.15	81.63	395.66	4.66	67.73
6145	1.25	1	-15	0	10.58	-6.82	11.39	16.77	21.64	1.7	73.94
5770	0.71	1	38	0	40.38	0	11.61	25.19	127.81	3.6	77.67
5157	3.33	1	19.5	0	99.96	19.72	11.27	70.37	340.08	4.5	77.67
5248	4.23	1	17	-1.4	99.96	22.19	11.15	78.85	370.68	4.58	81.4
5407	4.04	1	17.5	-1.4	99.96	22.19	11.15	76.26	354.68	4.56	83.26
5549	3.91	1	18	-1.4	99.96	22.19	11.15	74.81	357.23	4.56	83.26
5693	3.81	1	18.5	-1.4	99.96	22.19	11.15	75.63	361.06	4.58	86.99
5851	3.77	1	19.5	-1.05	99.96	22.19	11.15	76.25	377.74	4.62	90.72
6046	3.75	1	19.5	-1.05	99.96	22.19	11.15	77.14	377.74	4.6	90.72
6106	3.75	1	20	-1.05	99.96	22.19	11.15	77.87	377.1	4.6	95.69
6289	3.64	1	21	-0.7	99.96	22.19	11.15	77.83	377.1	4.62	95.69
6378	3.55	1	21.5	-0.7	99.96	22.19	11.15	77.73	375.81	4.6	99.42
6494	3.48	1	21.5	-0.7	99.96	22.19	11.15	78.31	375.81	4.52	103.15
5950	0.55	1	9	0	11.37	-8.41	11.27	8.75	14.38	1.52	103.15
5439	1.68	1	32	0	45.86	5.08	12.42	41.29	191.67	3.88	105.01
5619	3.8	1	19.5	0	99.96	22.19	11.15	82.53	380.31	4.62	106.88
5749	4.07	1	20	0	99.96	22.19	11.15	81.34	382.86	4.62	106.88
5840	3.88	1	20	0	99.96	22.19	11.15	78.69	371.96	4.6	108.12
5933	3.8	1	20.5	0	99.96	22.19	11.15	77.24	368.75	4.62	108.12
6002	3.74	1	20.5	0	99.96	22.19	11.15	77.04	372.6	4.54	110.6
5517	0.63	1	8.5	0	10.98	-8.27	11.15	10.41	29	2.04	113.71
4943	0.26	1	9	0	11.37	-10.59	11.15	7.33	22.3	1.84	113.71
4489	0.28	1	9	0	10.98	-10.88	11.5	5.68	18.32	1.8	114.95
4450	0.24	1	9	0	10.58	-11.17	11.5	5.69	19.08	1.78	114.33
4344	0.25	1	24	0	10.58	-11.31	11.85	6.48	17.94	1.76	114.33
* Registered users of the site do not see these ads.

Last edited by ohm; 01-19-2010 at 03:20 PM.
ohm is offline   Reply With Quote
Old 01-16-2010, 11:44 PM   #2
subiewrx001
Scooby Newbie
 
Member#: 193591
Join Date: Nov 2008
Chapter/Region: RMIC
Location: Salt Lake city, Utah
Vehicle:
04 WRX VF34
water/meth, spt intake

Default

do you have a front mount intercooler? if you dont those AFRs seem a little lean at WOT
subiewrx001 is offline   Reply With Quote
Old 01-16-2010, 11:49 PM   #3
dan az
Scooby Specialist
 
Member#: 120355
Join Date: Jul 2006
Chapter/Region: SWIC
Location: prescott valley, az
Vehicle:
2004 wrx wagon 2.5
20g-xt, super slow

Default

knock at that high a load and rpm I would be concerned about, and yea 11.6 is pretty lean for me.
dan az is offline   Reply With Quote
Old 01-16-2010, 11:51 PM   #4
ohm
Scooby Specialist
 
Member#: 178468
Join Date: Apr 2008
Location: Somerset, NJ
Vehicle:
2007 UGM STI
IAG Built

Default

Quote:
Originally Posted by subiewrx001 View Post
do you have a front mount intercooler? if you dont those AFRs seem a little lean at WOT
Nope. I am running an APS TMIC.

I should add that I am running 93oct and 50/50 meth.
ohm is offline   Reply With Quote
Old 01-17-2010, 10:45 AM   #5
ohm
Scooby Specialist
 
Member#: 178468
Join Date: Apr 2008
Location: Somerset, NJ
Vehicle:
2007 UGM STI
IAG Built

Default

With meth an AFR of 11.6 would be considered acceptable.

Another 3rd-4th-5th log with negative KC only in 3rd gear. Knock Learning is clean at 0, and DAM is 1.


Code:
RPM	Load	DAM	IADV	KC	KL	TP	Boost	AFR	IDC	MAF	MAFV	VS
2282	1.68	1	17.5	-1.4	0	99.96	2.03	13.11	12.41	64.64	2.54	25.48
2413	1.83	1	16.5	-1.4	0	99.96	3.05	12.31	13.54	74.81	2.72	26.72
2528	2.04	1	16	-1.05	0	99.96	4.21	12.65	15.8	83.46	2.78	27.96
2693	2.16	1	16	-1.05	0	99.96	5.51	12.77	18.59	101.12	2.98	27.96
2819	2.4	1	16.5	-1.05	0	99.96	7.25	12.65	20.85	113.94	3.14	30.45
3017	2.58	1	17	-0.7	0	99.96	9.86	12.88	24.84	135.88	3.44	32.93
3248	2.89	1	16	-0.7	0	99.96	13.78	11.39	37.78	164.03	3.64	32.93
3523	3.56	1	14.5	-0.7	0	99.96	20.45	11.15	48.28	232.98	4	36.66
3961	4.24	1	15	-0.35	0	99.96	22.34	11.15	59.63	294.28	4.22	40.39
4321	4.11	1	16	-0.35	0	99.96	22.34	11.15	62.53	303.12	4.28	40.39
4705	3.99	1	17.5	-0.35	0	99.96	22.34	11.15	65.86	314.64	4.32	45.36
5026	4.1	1	18.5	0	0	99.96	22.34	11.15	71.86	343.21	4.48	51.57
5357	4.07	1	19.5	0	0	99.96	22.34	11.15	77.18	363	4.54	51.57
5727	3.94	1	20	0	0	99.96	22.34	11.15	78.08	380.96	4.68	57.79
6015	3.83	1	21	0	0	99.96	22.34	11.15	78.65	391.21	4.64	64.62
6337	3.7	1	22.5	0	0	99.96	22.34	11.15	80.16	380.31	4.68	70.21
6624	3.55	1	23	0	0	99.18	22.34	11.15	78.57	381.59	4.6	70.21
5750	0.21	1	27	0	0	16.46	-7.98	11.39	7.41	35.35	2.22	75.81
5215	2.55	1	19.5	0	0	99.96	14.5	11.85	59.31	281.31	4.24	78.91
5152	4.32	1	19	0	0	99.96	22.34	11.15	81.77	377.1	4.62	78.91
5479	4.05	1	19.5	0	0	99.96	22.34	11.15	76.04	376.46	4.62	82.02
5570	3.99	1	19.5	0	0	99.96	22.34	11.15	76.72	352.14	4.58	85.13
5717	3.97	1	20	0	0	99.96	22.34	11.15	76.59	371.96	4.62	85.13
5842	3.87	1	20.5	0	0	99.96	22.34	11.15	77.46	371.32	4.58	88.86
6033	3.83	1	21	0	0	99.96	22.34	11.15	78.2	368.76	4.66	92.58
6164	3.75	1	21.5	0	0	99.96	22.34	11.15	78.01	374.53	4.62	96.31
6283	3.63	1	22	0	0	99.96	22.34	11.15	78.6	373.24	4.64	96.31
6445	3.59	1	22.5	0	0	99.96	22.34	11.15	79.47	372.6	4.62	100.66
ohm is offline   Reply With Quote
Old 01-19-2010, 03:26 PM   #6
ohm
Scooby Specialist
 
Member#: 178468
Join Date: Apr 2008
Location: Somerset, NJ
Vehicle:
2007 UGM STI
IAG Built

Default

Just an update after doing a bit of research on what exactly could be causing the -KC, which could be any number of things. A few posts that I read pointed towards the MAF sensor being dirty that would contribute to some poor performance, and -KC being triggered. I figured what the hell, so I checked to see how dirty it was, and sure enough it was caked with black grim after 30k miles. The IAT probe was especially dirty, so I cleaned it up real good, then did some datalogging. To my surprise the logs were clean, no -KC existed at all. I will be monitoring the next few days to see if cleaning the MAF really helped fix the problem for good.

3rd gear log

Code:
RPM	Load	DAM	IADV	KC	KL	TP	Boost	AFR	IDC	MAF	MAFV	VS
2196	1.12	1	35.5	0	0	26.66	-1.16	14.84	8.93	47.85	2.34	25.48
2267	1.33	1	28	0	0	34.5	0.58	13.57	11.74	52.7	2.48	26.1
2376	1.49	1	23.5	0	0	34.5	1.16	11.5	12.33	60.73	2.56	27.34
2496	1.61	1	20	0	0	39.98	2.03	12.31	13.44	70.48	2.7	27.34
2630	1.97	1	16	0	0	99.96	4.21	12.31	16.48	89.72	2.84	28.58
2799	2.17	1	16	0	0	99.96	5.66	12.53	19.18	105.99	3.02	31.07
2935	2.42	1	16	0	0	99.96	7.69	12.53	21.95	117.07	3.2	31.07
3144	2.57	1	16.5	0	0	99.96	10.73	12.99	26.48	141.02	3.38	32.93
3372	3.04	1	15	0	0	99.96	14.79	11.5	37.67	178.75	3.72	36.04
3700	3.71	1	14.5	0	0	99.96	22.48	11.15	51.39	243.72	4.12	36.04
4049	4.13	1	14.5	0	0	99.96	22.48	11.15	60.24	291.24	4.34	39.15
4443	4.1	1	16	0	0	99.96	22.48	11.15	62.34	312.81	4.32	44.12
4806	4.03	1	17	0	0	99.96	22.48	11.15	67.11	326.4	4.38	49.71
5125	4.05	1	18	0	0	99.96	22.48	11.15	73.14	359.14	4.58	49.71
5516	4.01	1	19	0	0	99.96	22.48	11.15	75.85	368.74	4.6	55.92
5803	3.84	1	20	0	0	99.96	22.48	11.15	77.36	380.95	4.64	62.14
6136	3.73	1	20.5	0	0	99.96	22.48	11.15	78.8	382.88	4.62	62.14
6384	3.6	1	21.5	0	0	99.96	22.48	11.15	79.2	388.01	4.6	68.35
5909	1.03	1	-15.5	0	0	11.37	-6.82	11.61	12.38	18.99	1.64	73.94
ohm is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
How come I Can't see feedback knock correction, fine learning knock correction? AraSh Open Source Reflashes 23 01-08-2014 08:04 PM
WTB 99 2.5 RS MAF sensor in SE WI STiluv55 Private 'Wanted' Classifieds 1 06-04-2010 08:20 PM
fbkc, knock sum, knock correction advance, help kh15 Open Source Reflashes 7 06-05-2009 01:56 PM
Correlations between Knock Lite and negative knock correction xFactor Engine Management & Tuning 1 01-12-2006 08:36 PM
MAF sensor dirty? QwikRex Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 4 04-21-2004 06:10 PM


All times are GMT -4. The time now is 10:37 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.