f1anatic Posted June 29, 2009 Share Posted June 29, 2009 I know it ain't normal. I have for now no logs to post - but I could get them. I have a CARPC and I have the knock correction as one of my displayed realtime data But i wanted to hear what experts got to say: on hot days (air temps 90 F) I get -0.5 to -2 timing at any rpm up to about 2500. Beyond that it turns positive, may go up to +9. If I reset the ECU, it will adapt (I suppose) and my timing correction stays zero. Until the next episode of hot weather when the negative values re-appear. Even today with air temps around 80 F, there was a -0.5 timing but as soon as I drove into the covered parking lot at work, on my way to 5th floor, my numbers leveled out to zero. Between my last pro-tune and now I added a Perrin TMIC (I was on stocker, stage 2 previously) and while the weather was still cool, there was nothing alarming. The issue is only at low rpm in hot weather and it is independent of the gas type. I suspect it is time for a re-pro-tune ? Is there anything else i can try ? Not the time I wanted to drop 200 dollars to P&L. Link to comment Share on other sites More sharing options...
caramall2 Posted June 29, 2009 Share Posted June 29, 2009 What is it displaying, FBKC or FLKC? Is it happening with WOT or partial throttle? What load? Link to comment Share on other sites More sharing options...
f1anatic Posted June 29, 2009 Author Share Posted June 29, 2009 I will log tonight on the way home. Pretty tough to do it while at work. The reported values are from Fine Learning Knock Correction if I am not mistaken. It happens at partial throttle. More so, it happens if I am using cruise control (which I do pretty often). Gosh what load ? I have that displayed but I cannot recall a value...Like today cruising at 60 mph (Cruise control) - 5th gear - 2500 rpm I would get -0.5 knock. I go to 4th, 0.00 knock, I go WOT in any gear, knock correction = +9 Link to comment Share on other sites More sharing options...
Spec B Posted June 29, 2009 Share Posted June 29, 2009 Low rpm, low load knock is very, very common. If your WOT runs are knock free I would not worry too much about it. Of course, to get a better understanding of what is going on some logs and a LV would help. Link to comment Share on other sites More sharing options...
f1anatic Posted June 30, 2009 Author Share Posted June 30, 2009 Can someone please have a look at my LOGS ? I would get knock at constant low rpm either at low speed (30 mph) or high speed (60 mph). I would not get it at WOT. I did several logs of each, presented in the Excel file I up-linked. Of course (to me) it is not showing the symptom: I did it in the evening when it is cold outside. Or at least to me they look fine. I hope the trained eye can spot something. Thanks. LOG Link to comment Share on other sites More sharing options...
Ridgeracer Posted June 30, 2009 Share Posted June 30, 2009 Must tuners do not rescale the low load timing region in their maps. "Gimme mines Balboa...Gimme mines".....Clubber Lang - Mr. T Link to comment Share on other sites More sharing options...
f1anatic Posted June 30, 2009 Author Share Posted June 30, 2009 I did some more driving this morning: the negative values that I occasionally see are in FLKC. I was able to see it but I am ashamed of myself since I thought I logged rpm but I did not. This was some city driving and then I got on the highway and stepped (WOT) on it in 3rd then 4th For the city section: What I can see is that if my KCA is (+) or (0), my FLKC is (0) or occasionally (-) but only when KCA is (+). FBKC always 0. Always under vacuum (no boost). For the highway section KCA goes to 9, FLKC to 0; FBKC alway 0; IAT to 9. So I am guessing the negative values that I see on my display are only FLKC. And what the hell is then that parameter that I am displaying ? The "any knock correction" values ? My dashboard displayed values are thru TreeHugger which is based on RR but obviously I am not entirely sure what it is ...cause it picks up the -1.4 from FLKC and the +9 IAT. So I guess it is the Knock Correction Advance, a fluid number which even if it is negative, it may not mean knock. Which brings the question: why have I not seen negs until now ? Is it the weather and my car loved the cold so much more than anyone else's that even my FLKC was 0 before the warm weather came ? Or did I mess something up on the car or the adding of the TMIC does need a new tune ? Is there a reason for my engine to blow up now or it will still be a little while ? Link to comment Share on other sites More sharing options...
Spec B Posted June 30, 2009 Share Posted June 30, 2009 I am sure your engine will last another 2 or 3 days max. You should download RR and log Knock Sum. That will show you exactly when you are knocking. What you are looking at now is the ecu's reaction to knock..not the knock event itself. Link to comment Share on other sites More sharing options...
rtbrjason Posted June 30, 2009 Share Posted June 30, 2009 You should download RR and log Knock Sum. That will show you exactly when you are knocking. What you are looking at now is the ecu's reaction to knock..not the knock event itself. +1, and learning view as well. Link to comment Share on other sites More sharing options...
f1anatic Posted June 30, 2009 Author Share Posted June 30, 2009 A'ight; I will see about it. I got RR and the logs come from it - maybe just did not see that parameter. LV will have to wait until tonight. Link to comment Share on other sites More sharing options...
f1anatic Posted July 1, 2009 Author Share Posted July 1, 2009 Is this the problem ? Look at my A/F Learning # 1 ? What does that mean ? MAF out of spec ? Dirty ? Or something more serious ? Retune needed ? I need some help guys. Plz. As for Knock Sum, I have the newest RR installed but I still don't see where I click to add it to the list of logged parameters. I re-loaded my pro-tuned real time map (I also have a pro-tuned base map) used and now I seem to produce some - FBKC when I start moving the car from a stand still after which it drops to zero and stays zero. Link to comment Share on other sites More sharing options...
Ridgeracer Posted July 1, 2009 Share Posted July 1, 2009 Your MAF could be scaled better. Drive around for 50 or so miles to let the car learn any FLKC. "Gimme mines Balboa...Gimme mines".....Clubber Lang - Mr. T Link to comment Share on other sites More sharing options...
f1anatic Posted July 1, 2009 Author Share Posted July 1, 2009 Your MAF could be scaled better. Drive around for 50 or so miles to let the car learn any FLKC. The car has about 40 miles on it before uploading the RTM and the learning view screen shot. I drove to work; I will go home and try cleaning the MAF (if that would make a difference) and will take another screenie. I am wondering what the problem is. I am no expert but it seems the car has only idle/low rpm problems not WOT. Link to comment Share on other sites More sharing options...
Spec B Posted July 1, 2009 Share Posted July 1, 2009 Your LV is completely clean of knock. That basically means (assuming your tuner did not mess with the ranges) that flkc is not pulling timing in anywhere. Your maf scaling is off but not horrible..ideally you want it under 5%, the only one that really matters is the 40+ range and that is at 0. Link to comment Share on other sites More sharing options...
f1anatic Posted July 1, 2009 Author Share Posted July 1, 2009 Hmm so are you suggesting that I can live like that ? Yes the ranges have been changed (I assume) by comparison to this http://www.legacygt.com/forums/showpost.php?p=2521749&postcount=17 Link to comment Share on other sites More sharing options...
Spec B Posted July 1, 2009 Share Posted July 1, 2009 My trim usually fluctuates between 2-4% in the first 3 ranges and less than 1% in the 40+ range. You should keep an eye on it, the 40+ range is the one you want less than 2% off. The LV's on that link are the exception..even stock you will see more trim than that. Link to comment Share on other sites More sharing options...
f1anatic Posted July 2, 2009 Author Share Posted July 2, 2009 I am confused. High Boost No Knock http://www.stimpco.com/upload/f1anatic/SUBARU-LGT/High%20Boost%20No%20Knock%20-%202.xls High Boost No Knock http://www.stimpco.com/upload/f1anatic/SUBARU-LGT/High%20Boost%20No%20Knock%20-%203.xls High Boost No Knock http://www.stimpco.com/upload/f1anatic/SUBARU-LGT/High%20Boost%20No%20Knock.xls Low Boost Some Knock http://www.stimpco.com/upload/f1anatic/SUBARU-LGT/Low%20Boost%20Knock.xls No Boost Knock http://www.stimpco.com/upload/f1anatic/SUBARU-LGT/Vacuum%20Knock%20-%202.xls No Boost Knock http://www.stimpco.com/upload/f1anatic/SUBARU-LGT/Vacuum%20Knock.xls Latest LV http://www.stimpco.com/upload/f1anatic/SUBARU-LGT/G%20LearningView_SS_7-1-2009%2010%2019%2051%20PM.jpg But i did see this http://www.stimpco.com/upload/f1anatic/SUBARU-LGT/D%20LearningView_SS_7-1-2009%207%2019%2008%20PM.jpg and this http://www.stimpco.com/upload/f1anatic/SUBARU-LGT/E%20LearningView_SS_7-1-2009%208%2036%2015%20PM.jpg as well as a completely clean table. http://www.stimpco.com/upload/f1anatic/SUBARU-LGT/F%20LearningView_SS_7-1-2009%2010%2002%2029%20PM.jpg Basically I get knock at low rpm, at the transition between vacuum and boost. But then I can also get knock when I am cruising, under low load/no boost/low rpm. Seems to be an issue at 2000-2500 rpm. Link to comment Share on other sites More sharing options...
Spec B Posted July 2, 2009 Share Posted July 2, 2009 Your tune is solid and your car is running fine. The knock you are getting is normal... Keep an eye on your LV though...the fuel trim adjustments should be a little lower. Link to comment Share on other sites More sharing options...
weitek Posted July 5, 2009 Share Posted July 5, 2009 Is the knock happening under vacuum? The same thing happens on my car and several others that I have logged/tuned. I have experimented with this on my own car by pulling out up to 10 degrees of base timing and it would still report knock, mostly during cruise on the highway, never under boost/load. I even tried flashing back to the stock map and it was still doing it - really frustrating. There doesn't seem to be much info out there about this (at least I couldn't find much) but I have come across a few posts on the RomRaider forums suggesting it's a> normal and b> harmless (as long as it's happening at low load/rpm/under vacuum). I got sick of my car always pulling timing so after I had tried everything else and I checked all the mechanical stuff I just raised the knock correction threshold values to ignore it. Since I run much less timing than stock below 1 load and I log my car very often I am not worried about it. I currently have it set to ignore knock below 1.05 load and it drives a lot smoother since it's not pulling timing all over the place, and a nice bonus is I don't have to look at a bunch of bogus un-fixable knock in my logs. I also don't run any advance in those areas so I don't have to worry about it advancing out of control and causing problems. I have a feeling there is some noise in my engine bay (perhaps a heat shield or something) that causes false knock but I really don't know as I've seen it on several other cars. Please note I don't claim to be an expert or the greatest tuner out there so I advise you to do your own research and carefully consider any changes but for me that was the best solution and I am really happy with the results. Also I agree with the other guys you should try to adjust your MAF a little closer if possible. I don't think it is the cause of your issue but your car will idle/drive a LOT smoother if less A/F correction/learning. Also I'm not sure if the Cobb Race Tuner software allows you to adjust that but if you have a V2 AP you could download it for free and check. Good luck. Link to comment Share on other sites More sharing options...
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