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BTSSM says I have knock


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Same here. I'll post the compression test results right after. Tuning Alliance said that if the numbers are good then it's likely too much air vs fuel because of the mods causing the knock. So, they recommended a new high flow DP and a Cobb AP tune with the intake mods I have so everything breathes better. Which is a lot cheaper than me having to get another car or a shortblock.

Still astounds me the tune was never advised til now.

 

Understood.. it's one of those things that is brought up a bit (getting a tune with any upgrades, or possibly even bone stock), but is not always apparent. Sounds like Tuning Alliance's advice is great, and something to hope for (no damage, just get tuned and make a choice mod or two). I'm sure it'll be a nice bump in power.

BtSsm - Android app/Bluetooth adapter. LV, logging, gauges and more. For 05-14 Legacy (GT, 2.5, 3.0, 3.6), 02-14 WRX, 04-14 STi, 04-14 FXT, 05-09 OBXT
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I hope for that too. I've spent the last four and a half years with this car and I really don't want to give it up. Plus it has a brand new VF40.

I have to really thank the BtSsm app for everything it does cause I would have been stupidly unaware.

On the plus side I've read that oil consumption is a symptom of ringland. I don't have that.

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The shops I go to for the majority of my work.

I had the stock TMIC start to seperate so the shop that handled a suspension install hooked me up a knock off Process West TMIC kit. Then I couldn't stand the fitment issues and the fact it was a knockoff and then bolted in the GrimmSpeed TMIC myself. Then every shop I've been to never asked til BtSsm said I had knock and then I asked them to check that out.

In other news as long as I drive like I'm 95 the knock warnings go away. I drove home from work and the counter only hit 5 with no warnings.

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well keep babying it then, and/or driving like you're 95. either extreme, baby or old, just not in between.

 

btw you should probably tend to ignore the "knocks" field. Not all ECUs even have it. It's a very raw counter of knocks, and seems to count a LOT of false knocks. Definitely FKC, FLKC (reflects LV timing pull), and IAM (sb always 1) are the ones to watch.

 

considering dropping the knocks field from the app since it mainly seems to cause stress rather than helpful info.

BtSsm - Android app/Bluetooth adapter. LV, logging, gauges and more. For 05-14 Legacy (GT, 2.5, 3.0, 3.6), 02-14 WRX, 04-14 STi, 04-14 FXT, 05-09 OBXT
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There's some older logs posted as attachments.

 

Learned Values are from today. As well as these recent knock events. While I was driving like I was 95. Can anyone explain why I have LV parts in red? I know it's bad I just want to learn why.

 

KNOCK DETECTED at 2016-03-14 05:19:34 PM

AFR: 14.6

AFR (lambda): 0.99

Battery (V): 14.2

Boost (psi): -3.90

Coolant (degF): 183

FKC (deg): -2.11

FLKC (deg): 0.00

Fuel correct (%): -5.0

Fuel learn (%): 12.50

Fuel pump DC (%): 33.3

IAM: 1.000

Injector DC (%): 5.5

Injector PW (ms): 4.1

Intake (degF): 59

Knocks: 9

Load (g/rev): 0.63

MAF (g/s): 16.86

MAF (V): 2.00

Misfire cyl 1: 0

Misfire cyl 2: 0

Misfire cyl 3: 0

Misfire cyl 4: 0

O2 rear (V): 0.8

RPM: 1598

Speed (mph): 26.7

TGV left (V): 0.34

TGV right (V): 0.40

Throttle pedal (%): 7.8

Throttle plate (%): 13.7

Timing (deg): 27.0

VVT int L (deg): 11

VVT int R (deg): 11

 

 

KNOCK DETECTED at 2016-03-14 05:17:04 PM

AFR: 14.5

AFR (lambda): 0.98

Battery (V): 14.1

Boost (psi): -3.60

Coolant (degF): 181

FKC (deg): -2.11

FLKC (deg): 0.00

Fuel correct (%): -0.3

Fuel learn (%): 12.01

Fuel pump DC (%): 33.3

IAM: 1.000

Injector DC (%): 6.4

Injector PW (ms): 4.4

Intake (degF): 59

Knocks: 8

Load (g/rev): 0.63

MAF (g/s): 18.20

MAF (V): 2.04

Misfire cyl 1: 0

Misfire cyl 2: 0

Misfire cyl 3: 0

Misfire cyl 4: 0

O2 rear (V): 0.6

RPM: 1736

Speed (mph): 37.9

TGV left (V): 0.34

TGV right (V): 0.40

Throttle pedal (%): 8.2

Throttle plate (%): 14.1

Timing (deg): 29.0

VVT int L (deg): 11

VVT int R (deg): 12

 

 

KNOCK DETECTED at 2016-03-14 05:13:46 PM

AFR: 14.9

AFR (lambda): 1.02

Battery (V): 14.2

Boost (psi): -3.40

Coolant (degF): 185

FKC (deg): -2.11

FLKC (deg): 0.00

Fuel correct (%): -1.3

Fuel learn (%): 9.23

Fuel pump DC (%): 33.3

IAM: 1.000

Injector DC (%): 5.5

Injector PW (ms): 4.4

Intake (degF): 59

Knocks: 6

Load (g/rev): 0.68

MAF (g/s): 16.98

MAF (V): 1.98

Misfire cyl 1: 0

Misfire cyl 2: 0

Misfire cyl 3: 0

Misfire cyl 4: 0

O2 rear (V): 0.8

RPM: 1489

Speed (mph): 19.3

TGV left (V): 0.34

TGV right (V): 0.40

Throttle pedal (%): 9.4

Throttle plate (%): 14.5

Timing (deg): 25.0

VVT int L (deg): 8

VVT int R (deg): 8

 

 

KNOCK DETECTED at 2016-03-14 05:11:46 PM

AFR: 14.9

AFR (lambda): 1.02

Battery (V): 14.2

Boost (psi): -3.60

Coolant (degF): 186

FKC (deg): -2.11

FLKC (deg): 0.00

Fuel correct (%): 0.6

Fuel learn (%): 12.50

Fuel pump DC (%): 33.3

IAM: 1.000

Injector DC (%): 5.7

Injector PW (ms): 4.4

Intake (degF): 59

Knocks: 4

Load (g/rev): 0.67

MAF (g/s): 17.54

MAF (V): 2.00

Misfire cyl 1: 0

Misfire cyl 2: 0

Misfire cyl 3: 0

Misfire cyl 4: 0

O2 rear (V): 0.9

RPM: 1568

Speed (mph): 30.4

TGV left (V): 0.34

TGV right (V): 0.40

Throttle pedal (%): 8.2

Throttle plate (%): 13.7

Timing (deg): 26.5

VVT int L (deg): 10

VVT int R (deg): 10

BtSsm_LV_20160314_1723.png.c28b27e0eb8c9f23f560d3dc4bd80065.png

BtSsm_20160311_231729_knock.csv

BtSsm_20160309_174120.csv

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Positive values mean that the ECU is adding x% of fuel to the mixture because it noticed that there was unmetered air getting into the chamber. As mentioned before, it could be from a vacuum leak, or a tune that needs to be adjusted for the newly installed aftermarket parts. Acceptable values are between +/-5%.
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Positive values mean that the ECU is adding x% of fuel to the mixture because it noticed that there was unmetered air getting into the chamber. As mentioned before, it could be from a vacuum leak, or a tune that needs to be adjusted for the newly installed aftermarket parts. Acceptable values are between +/-5%.

 

I'm pretty sure the compression and leakdown test will find out where the leak is coming from. I've checked for them and can't find them. Neither can my usual shop. Now, if the numbers are good and the engine healthy I will be ordering a new downpipe and a custom tune through another respected shop in the area. Thursday will tell and I'll post results here.

 

Once again. Thank you to everyone for helping me understand all of this and narrow down the cause.

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I'm pretty sure the compression and leakdown test will find out where the leak is coming from. I've checked for them and can't find them. Neither can my usual shop. Now, if the numbers are good and the engine healthy I will be ordering a new downpipe and a custom tune through another respected shop in the area. Thursday will tell and I'll post results here.

 

Once again. Thank you to everyone for helping me understand all of this and narrow down the cause.

 

Are they going to be checking for vac/boost leaks as well?

 

The compression/leakdown is to check for ringland failure/general engine health. If they have a smoke machine that is the way to go.

 

You'll need to get that LV cleaned up before you get a tune.

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General engine health will be looked at and another vacuum and boost check since it's running lean. I'll double check on the smoke machine tomorrow since they're closed by now.

I know this'll sound like a stupid question , but running this way would change my fuel economy? It went down after I got the brand new VF40 put in. Up until that my car was really happy and sipped rather than drank.

LV will be cleaned up before a tune. Though it came across to me as that could be my possible fix.

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I also want to ask, could anything else cause my LV numbers to be the way they are. I'm looking things up and is there anything else that could cause the numbers to be this far off? Just IF there isn't a vacuum leak.

O2 sensor is my next guess, maybe the MAF, maybe the O ring for that?

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UPDATE:

 

Just got back from the shop. Compression tests are good 153 PSI for all four cylinders. The Leakdown test was not so good. 5% from #1-3 and #4 has a 11% loss. IAM has dropped to 0.500 and I'm staying out of boost and driving the car as minimal as possible.

 

I'm looking at loans so I can save this car with a new shortblock, get a downpipe, catback, and get a custom tune.

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Well, when they gave you the leakdown test results, did they specify where it was leaking from for each cylinder?

 

If they did not specify where it was leaking from, then the only sure way to find out is by checking your valve clearance.

 

But again, log or view live the 'misfire' per cylinder parameters and see if you get any counts at cold or warm idle, or while you drive and report.

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I will ask again in the morning about the leak results. I did not know at all you could specify where the leak is from for each cylinder. This gives me some renewed hope.

 

I will also report with misfire results. Every knock warning reports no misfire.

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when they do a leakdown test, they blow compressed air into the cylinder (from the spark plug hole) while the valves are closed and the piston is at TDC.

Say an intake valve is leaking, you will then hear air hissing through the air intake. If an exhaust valve is leaking, you will hear air escaping through the exhaust. If the rings are shot, you will hear air coming out of the oil cap (although in most leakdown test, some air almost always pass the rings).

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Yep. I got a misfire warning from Cylinder 4. Time to just park this car for a while.

I asked about the leak down and they said they were not 100% sure it was a valve or the cylinder. Just that #4 leaks 11-13%

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Not a single CEL or warning on the standard gauges. Just the one misfire count from cylinder 4 on startup. I was doing some reading and a leaking or burnt valve can lead to cylinder damage if I read that right. If the bank approves me I'm going with an EJ257 block and remachined heads along with a bunch of other new parts.

 

https://scontent.xx.fbcdn.net/hphotos-xlp1/v/t1.0-9/1451963_581296195369062_3391148135649796342_n.jpg?oh=aabc7d4285d684cd8c8e6609ce1df748&oe=578B2AF6

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There is a tiny chance that it could be the #4 injector is going bad, or maybe the #4 coil. If you have a pretty reliable misfire on cyl 4, you could always try to move the #4 injector (swap with #2 for example) to see if the misfire moves with it. If so, you found your problem. If that doesn't help, try same with the #4 coil.

 

I tend to grasp for easier explanations that "you need a new short block" - although that often is the answer.

 

EDIT: if it was only a single misfire count, please disregard above

BtSsm - Android app/Bluetooth adapter. LV, logging, gauges and more. For 05-14 Legacy (GT, 2.5, 3.0, 3.6), 02-14 WRX, 04-14 STi, 04-14 FXT, 05-09 OBXT
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So you only had a count of 1 on the misfire gauge on the btssm for cylinder 4? Then that is no cause for concern. A count of 1 is nothing to worry about really. The check engine light will usually turn on if the misfire count will go up to 30-45.

 

So I would say, monitor the misfire count per cylinder on cold idle, and warm idle. And report.

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Defo check inlet leaks, there's a variety of methods the simplest being to use soapy water spray in the bay whilst the car is being revved gently.

Check all the vac hoses and maybe the fuel Evap purge control solenoid too.

Use a new o ring on the maf and make sure it's seated properly, as they kink easily. If it's difficult freeze the maf & o ring together in the fridge for 10 min to shrink the o ring a little before reinstalling it with a little lube :)

When you have the affected coilpack out, twist the loom pins slightly to promote continuity to the loom plug :)

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