*** Knock, do you have any?

[iNVAR]

I'm not talking about the knock. I'm talking about your AF trims drifting positive.

[Chris GTO TT]

Oh well they have always been that way... In fact that's the lowest I've seen them in awhile. It's just an ots tune from an e-tuner.

[fishbone]

Hi guise!

Moved from Lincoln NE to TX, which means the car has moved from crappy 91 to 93 octane. I've put 1K miles on it already and am datalogging like a madman.

So far all the FLKC I've been seeing in NE in the last years that have caused me much head scratching and concerns, appears to be noise. It's still there in the tune, same amount, same spots. Gonna give it a few more driving cycles and will pull a LV even though it should be beyond well established by now.

[lingling1337]

Hi guise!

Moved from Lincoln NE to TX, which means the car has moved from crappy 91 to 93 octane. I've put 1K miles on it already and am datalogging like a madman.

So far all the FLKC I've been seeing in NE in the last years that have caused me much head scratching and concerns, appears to be noise. It's still there in the tune, same amount, same spots. Gonna give it a few more driving cycles and will pull a LV even though it should be beyond well established by now.

 

My tuner also attributes my knock to tranny noise. Btw, unless they're lyin about the rating, fantasy's gas sells 93 in NE.

[fishbone]

I was strictly talking about Lincoln, not all of Nebraska. If there are 93 octane pumps left, they are at most a handful in obscure locations.

[fishbone]

Don't have LVs but I'm still seeing the same amounts of FLKC learned in the exact same conditions on 93 as when I was running 91. I am going to conclude, after having watched it with some concern for many years, it is false knock and will raise the FLKC accordingly and drop FBKC threshold to 0.9 or something just to cover my base, in case it is not already set there.

It happens at or below 1.3 load, engine under vacuum, relatively light throttle, around 2800-3200rpm. Looks a lot like the cruise knock many are seeing. Good news is I've not seen IAM drop for about a hear and half now.

[crankshift]

if I buy an AP just to log data am I limiting myself or will I be missing anything critical?? My plan is to get a pro tune after I put on some bolt on parts but I want to do my own logging and right now I feel an AP is the easiest way after a good amount of (but not all) reading as I dont plan or want to get heavily involved with tuning...

 

Any insight here would be great!! I found a nice deal on a AP for 300 bones... Would it make more sense to invest in the other logging methods (cables, software, whatever else is needed) stuff? what is the typical cost on this other gear? I want to spend the least amount but log everything that is required to be safe and I want the easiest method to do so.

 

I believe the pro tuner closest to me will do free touch ups for minor little things so I am planning on not making any little adjustments myself down the road(if the logs permit alterations) but anything major or new parts added will be another chunk of change of course..

 

Thanks for any input and feel free to suggest I post this somewhere else if I got it wrong... Thanks very much!!

[fishbone]

If you want to spend the least amount then look for a used laptop. But this also depends on the tuner, if the tune will be open source or not.

[iNVAR]

If you're not planning on using the AP in your car to switch maps or look at live data etc. etc. and you only want logging, you should be buying a Tactrix cable and using your laptop to flash if necessary. This has been covered a lot here already. However, if your tuner is only willing to work with the AP, well, that limits you to the AP only. Ask your tuner if OS is even an option first.

 

There are Tactrix cables that can log without a laptop as well.

 

The main attraction of the AP is having the ability to view data while it's hooked up and to be able to make realtime adjustments and map changes. It doesn't sound like you'd be doing that.

 

Also, the logging interval on the AP is lower, and I don't know if that was ever changed by Cobb. Last I noticed the logging interval was between 200-300ms on a limit number of parameters whereas with a Tactrix cable and RR you could do about 100ms with 20+ parameters.

[crankshift]

alright thanks, this helps a lot and I have a direction for my reading now

 

Thanks!

[caramall2]

This may have been mentioned, but the old Cobb article on knock monitoring had some good info and clarification IMHO. It just adds to the good info here on this thread. Sorry if someone already posted it.

 

https://static.cobbtuning.com/cobbtuningweb/site/support/techdocs/Subaru%20Knock%20Monitoring%20FAQ%20v2.pdf

[BoozeRS05]

Anyone mind looking this log over for me?

 

Cobb stg2 91oct map, but running Sunoco 93oct. Mod list is pretty typical - Cobb DP, GS UP, stock intake, SPT cbe. Boost maxes out around 16psi. I have a decent leak at the CBE, maybe a leak before the turbo too.

datalog13.csv

[iNVAR]

Looks fine to me. Typical minor knock from OTS map, not a big deal since it's when you're at the onset of WOT. Start log from 2K next time. What's humidity/temp and elevation like there?

[BoozeRS05]

Thanks for a quick reply.

 

>1000 ft elevation, mid 70's, 70% humidity.

[iNVAR]

Np.

 

You're only off by 0.5 psi in 3rd gear, that's really nothing, especially with the slightly higher elevation and moderate humidity, and the later start in your pull (2.5K instead of 2K). Looks fine. A CBE leak won't affect your boost. A pre-turbo leak might though.

 

Do another few pulls if you're bored and have time, and also log Intake Temp please.

[stm25rs]

I just installed my Cobb AP v2 yesterday, did a couple of logs today, which are attached. That's kind of a lot of knock at high load right? Stage 1, 91 octane map, car is stock.

 

I'm gonna install the Cobb Stock Mode map and do some more logs...and probably think about who I should get an e-tune from.

datalog2.csv

datalog3.csv

Edited November 3, 2013 by stm25rs

[SeeeeeYa]

I just installed my Cobb AP v2 yesterday, did a couple of logs today, which are attached. That's kind of a lot of knock at high load right? Stage 1, 91 octane map, car is stock.

 

I'm gonna install the Cobb Stock Mode map and do some more logs...and probably think about who I should get an e-tune from.

 

You're right, that's terrible. Something is wrong, somehow, somewhere.

 

You're also correct in putting the stock map back and logging to see if you can learn anything from that, and very importantly, seeking professional help with tuning your car. The current path is definitely not good.

 

I hope you are using 93 octane fuel... along with a 91 octane map, although that would make the logs even worse. Point is, your engine NEEDS 93 octane fuel. Do not try to use 91 out of economic considerations if 93 is available. You engine will not like that.

[stm25rs]

You're right, that's terrible. Something is wrong, somehow, somewhere.

 

You're also correct in putting the stock map back and logging to see if you can learn anything from that, and very importantly, seeking professional help with tuning your car. The current path is definitely not good.

 

I hope you are using 93 octane fuel... along with a 91 octane map, although that would make the logs even worse. Point is, your engine NEEDS 93 octane fuel. Do not try to use 91 out of economic considerations if 93 is available. You engine will not like that.

 

I only run 93 octane. I started with the 91 map because I've read that the some have knock with the OTS maps. It was definitely faster, but I won't be running the stage 1 ots again.

 

The car's just under 135k, I bought at 125k, and has never been modified.

 

Logs from the Cobb stock map are attached. I didn't get as good of pulls, and didn't get up to 6500 rpm, but it the only knock shown is at peddle lift off. I had the live monitor showing knock sum, and when cold, it was recording knock when in neutral coming to a stop.

 

As far as logging parameters, are there any extra I should be logging, or any I can remove?

datalog6.csv

datalog8.csv

[serx7]

Your logging sample rate is kind of slow, although I usually don't see big improvements in polling speeds even when paring down the # of parameters.

 

datalog8.csv actually shows FBK being registered at the 9.49 sec mark, at 5563 rpm, with throttle recorded as still being 100%. Immediately after that, you lift. I'm not sure if that's just an artifact of the AP logging speed, or if there was actually knock @ WOT just before you lifted.

 

seeing knock sum increment doesn't mean you had knock.

 

what gas (brand) are you using? your logs remind me of what I saw in my '05 Saabaru 9-2X Aero (basic Stage 2 mods, Cobb Stage 2/93 oct OTS map) when I filled up at a local Valero station a long long time ago. i ran that tank way down gently, and filled up w/ Shell 93, and never saw that kind of knock again. as a test, i ran the Shell tank way down, filled up ~1/3 tank at the Valero, and the knock almost immediately returned. the car never saw Valero gas again. i see similar behavior w/ my '05 OBXT (built motor, VF52, IPR TMIC, Cobb catted DP, Nameless midpipe/y-pipe, protune, etc). i see intermittent but somewhat repeatable knock at high load and mid-high RPM w/ the local Shell 93 gas, but no such knock in identical ambient conditions w/ the local Sunoco 93. normally i'd pull a deg out of the base timing map in the 'problem' areas for a little more margin of safety, but since I pass that Sunoco station every morning, i don't have to worry about having to fill up elsewhere.

[stm25rs]

Your logging sample rate is kind of slow, although I usually don't see big improvements in polling speeds even when paring down the # of parameters.

 

datalog8.csv actually shows FBK being registered at the 9.49 sec mark, at 5563 rpm, with throttle recorded as still being 100%. Immediately after that, you lift. I'm not sure if that's just an artifact of the AP logging speed, or if there was actually knock @ WOT just before you lifted.

 

seeing knock sum increment doesn't mean you had knock.

 

what gas (brand) are you using? your logs remind me of what I saw in my '05 Saabaru 9-2X Aero (basic Stage 2 mods, Cobb Stage 2/93 oct OTS map) when I filled up at a local Valero station a long long time ago. i ran that tank way down gently, and filled up w/ Shell 93, and never saw that kind of knock again. as a test, i ran the Shell tank way down, filled up ~1/3 tank at the Valero, and the knock almost immediately returned. the car never saw Valero gas again. i see similar behavior w/ my '05 OBXT (built motor, VF52, IPR TMIC, Cobb catted DP, Nameless midpipe/y-pipe, protune, etc). i see intermittent but somewhat repeatable knock at high load and mid-high RPM w/ the local Shell 93 gas, but no such knock in identical ambient conditions w/ the local Sunoco 93. normally i'd pull a deg out of the base timing map in the 'problem' areas for a little more margin of safety, but since I pass that Sunoco station every morning, i don't have to worry about having to fill up elsewhere.

 

I'm pretty sure my last couple of tanks have been Exxon. I avoid the no-name brand stations, and typically stick to Shell, Exxon, or BP.

 

I've started a Stage 1 e-tune with one of the vendors here. Just logged my Stage 1 revision last night. There was still a little bit of high load knock, although not as much as Cobb's Stage 1. Peak boost on this Rev was only 13.5 psi. I'll post some logs once the tune is done.

 

edit - Bren just got back to me after reviewing the Rev 1 logs, and says it looks like I'm in need of a fuel pump.

Edited November 6, 2013 by stm25rs

[caramall2]

I'll let more knowledgeable folks chime in but I would both a) check knock and, b) check AFRs under full throttle with a wideband sensor. This should help confirm if there are fuel delivery issues in that state.

[stm25rs]

I'll let more knowledgeable folks chime in but I would both a) check knock and, b) check AFRs under full throttle with a wideband sensor. This should help confirm if there are fuel delivery issues in that state.

 

Car is stock, I don't have a wideband sensor, but the log Bren looked at included knock and AFR. The AFR was pegged at the sensor's low limit (11.x) at max load and high RPM, which is when the knock occurred.

 

I was planning on going to a DW65c when I eventually upgrade the turbo anyway, so not a big deal.

[Stony_Danza]

Ok, been trying to do my part and learn as much about these things as i can since I bought my LGT, but I figure if people here are willing to help, then I should at least ask. Today I noticed a lot of -5.60 FKL while live monitoring my AP. I've never seen this before, and wondering if it's bad. Yesterday I drove from Ft. Bragg, NC to Oak Ridge, TN and took the Cherohala Skyway (tons of fun), but today, just cruising around town I noticed when I let up on the pedal after a quick acceleration, the FKL would jump to -5.60 and stay there for a moment. I immediately logged it and was careful to avoid it again until I got back to the hotel. Here's the log I grabbed. It's stock with a Cobb OTS 93 octane stage 1 map. If anyone could be nice enough to look and give their 2 cents I'd appreciate it.

datalog10.csv

Edited November 10, 2013 by Stony_Danza

[serx7]

Most of that feedback and fine learning knock is at relatively low load and low RPM. Might want to see if you've got a heat shield rattling under the hood or something like that.

 

The fine learning knock -1.05 around 3500 rpm and 2.5 g/rev load, might be real knock though.

[crankshift]

close to stock (only has an STI up pipe and vf46 in there) 05 LGT 5EAT here and this is one of the first logs I have taken when I loaded the cobb OTS 91ACN map for the first time (never loaded any other map to it yet). Wondering if this is fine to be running for a month or two before getting tuned..

 

my only mods planned for tune time are going to be hexmods 5eat valve body which will be installed first (not even sure if this will impact anything tune wise or not) and then a week or two later the catted cnt downpipe, perrin TMIC and the cobb intake + air box will be done all at once w/ the tune....now that I have all of these parts here I am also tempted to just getting on with the installation right now and moving on to the next map

 

here is a log, thanks for any feedback!

datalog8.csv