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Discussion Starter · #1 · (Edited)
So, just as the title says, I'm getting strange readings. I never had a protune done before, I just bolted on some parts and flashed the ECU with the Accessport. :confused:

Vehicle Information:
2008 STi
105, 677 Miles
103, 440 Last Oil Change
103, 879 Spark Plug Change
104, 789 Last Coolant Change w/ Super Coolant (50/50) and Conditioner

-Parts:
COBB SF Intake
NGK Iridium Spark Plugs gapped at .028
Nameless Muffler Deletes

-Tune:
Currently- Stage 1 + SF Intake 91Oct (OTS) [Changed due to issues = temporary fix]
Previously - Stage 1 + SF Intake 93Oct (OTS)
Experimented with Stage 1 Economy Mode (OTS) [had a long trip wanted log changes in MPG, if any]

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Background Information:

I took a long trip from Northern New York to Philadelphia, PA (289 Miles) on Stage 1 Economy Mode (OTS) just to see if any changes to MPG would surface... Starting suspect that I am going to regret this decision. :unhappy: So, going down, was no problem at all. Upon coming back up, half way through my trip, I noticed "sputtering" in the sense of a jerking due to a loss of power during acceleration in 5th/6th Gear. Noticed huge drops (increase depending if you perceive negative values) in Feedback Knock (as low as -11.80!!! :unhappy: ) and Fine Knock Learning ( as low as -11.77!!! :confused: ). At one point, the DAM dropped to 0.550!!! I noticed that whenever Boost was being dumped, the FBK and FKL would make those huge NEGATIVE VALUES. I suspected that it was my map and Changed back from Economy Mode to Stage 1 + SF Intake 93Oct IMMEDIATELY!!! :shakehead: I waited around 15 minutes at the toll booth because I was nervous, then pulled off and had very minor "sputtering" instances but not as much instances as huge negative values as before.

As I further did some investigations, I figured it was time to change those Spark plugs. I was right. The old ones were completely brown and had tons of carbon build up. Installed the NGK Iridiums gapped at 0.30 (for longer life expectancy) and things ran smoothly for a few days. Then.... the "sputtering" again. :mad: It caused extreme negative values and I knew that I needed to regap the Plugs to the factory 0.028, I realized that the mistake must have been a foolish move. Damn, I'm starting to second guess everything I'm doing!!! :mad: Upon regapping, I realized that the Coil Pack on Cylinder 1 had loosened since the last Spark Plug Change!! HOW?! Again, my face: :mad: At this point, I'm about to take a sledge to my motor... but wait... that's not what makes a Subaru owner a Subaru owner.... :pray:

So, I fix the gapping issue, and it ran ****ing great for a week! No negative FBK or FKL values lower (or greater, again, depending if you read negative values appropriately) than -2.8. No power losses, neither in 3rd Gear WOT's or Highway Cruising (65 to 78 MPH). Then, the "sputtering, jerking, no-boost-gain-acceleration-that-pushes-you-into-the-seat-feeling, and low rumble (not-as-throaty-or-loud-out-the-rear) noise" came back to rear it's ugly *&^%!#@ head!!! :mad: :mad: :mad: It's about to be a RIP RIP on this motor and my patience for it.... But, again, WWASOD (What Would A Subaru Owner Do?) :pray:

Finally, I give up and read a ton of articles on these extreme negative values from COBB posted on their website that someone transcribed and posted to NASIOC [ Click Here: https://forums.nasioc.com/forums/showthread.php?t=2711703 and do a search/ Find In Page for "extreme negative values" ]. So, it seemed to be a Boost Leak issues.... But, really??? REALLY?! Hmm... :confused:

I called COBB, but they're taking forever to review the email I sent them with the Datalogs and I need answers!!! Recently, the DAM has been dropping and the FKL has been dipping again into the -5 to -9.8 range. :eek3:

I'm going to post the Datalogs and see if anyone can offer me answers, and preferably, SOLUTIONS!!! :pray:

Thanks ahead of time!!!


FILES
WOT 3rd Gear Pull w Low DAM and POS FKL : https://drive.google.com/open?id=0B4draOa__qd7ZUZpbmNTT2hWZnc VERDICT?!- :D
HIGHWAY DRIVING 91Oct w SF OTS Map : https://drive.google.com/open?id=0B4draOa__qd7M3BuOHdxS0FNUXM VERDICT?!- :confused:
Regular City Driving w Jumping FBK and FKL : https://drive.google.com/open?id=0B4draOa__qd7ZXVPWktZX3FqbTQ VERDICT?!- #$&! :mad:
 

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First. You need a timing belt.

I would look into intake or boost leaks first.

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Discussion Starter · #3 ·
First. You need a timing belt.

I would look into intake or boost leaks first.

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I appreciate that. I know that Subaru recommends Timing Belt Replacements at 105, 000 Miles, but I experienced the "sputtering" at 101, 000 Miles.

4, 000 Miles sooner, I'm assuming, is normal. Correct?

I appreciate the quick response.
 

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I wouldn't keep driving it until you I'd the culprit and put a timing belt on the car. Typically timing belts don't show signs of wear with misfire, they just break and on an interference engine like ours total the valve train, pistons, and combustion Chambers in extreme cases.

My personal plan of attack is find a shop to do the timing belt, while there have the intake tract from the maf to the block tested for vacuum or boost leaks, I would also have compression and leak down tests performed.

If everything comes back positive you know it's a sensor, fueling, or coils.

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Discussion Starter · #5 ·
I wouldn't keep driving it until you I'd the culprit and put a timing belt on the car. Typically timing belts don't show signs of wear with misfire, they just break and on an interference engine like ours total the valve train, pistons, and combustion Chambers in extreme cases.

My personal plan of attack is find a shop to do the timing belt, while there have the intake tract from the maf to the block tested for vacuum or boost leaks, I would also have compression and leak down tests performed.

If everything comes back positive you know it's a sensor, fueling, or coils.

Sent from my SAMSUNG-SM-G935A using Tapatalk

G.O.A.T. !

That's some great points you have there. I've been so caught up with everything else that I been completely disregarding the belt issue.

Thanks for putting some perspective and clarity to my frustrations. I wasn't thinking clearly and overlooking the obvious.

I'll get the timing belt changed and do the EVAP/BOOST/VACUUM Leak test just to clear everything up.

Did you happen to take a look at my logs and notice anything else crazy?
 

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I am not an expert at data logs. I would not feel comfortable giving you advice off of what I read there. I understand enough to know what the numbers mean, but not enough to feel comfortable providing advice about it.

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Discussion Starter · #7 ·
I am not an expert at data logs. I would not feel comfortable giving you advice off of what I read there. I understand enough to know what the numbers mean, but not enough to feel comfortable providing advice about it.

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Fair enough! I appreciate it!

Thanks again!
 

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I would just garage the car until this is addressed. Your D.A.M numbers alone are startling.

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Your timing belt is an issue. But it is not causing any of these problems I wouldn't think.

Your car is pulling global timing, that means knock is a serious issue continuing with a damn less than 1 is bad news.

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Discussion Starter · #12 ·
Your timing belt is an issue. But it is not causing any of these problems I wouldn't think.

Your car is pulling global timing, that means knock is a serious issue continuing with a damn less than 1 is bad news.

Sent from my SAMSUNG-SM-G935A using Tapatalk

Mmm... I already anticipated this being a bigger issue than just a belt and Boost Leak...

I'm guessing it may be a catastrophic failure of some sort... Ringland... Head Gasket... Cracked Piston... etc. etc. etc.....

RIP RIP!!! Well..... It was a good year....
 

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Just curious: Have you owned this car since new?



Compression / Leakdown tests
Boost leak test

See if there's a mechanical issue you need to address.
 

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Discussion Starter · #14 ·
Just curious: Have you owned this car since new?



Compression / Leakdown tests
Boost leak test

See if there's a mechanical issue you need to address.

That's what I was thinking on the Boost Leak Test.

Good call on the Compression Test.

Did you make that call by observing the Datalogs?

I'm just asking to get to the bottom of these numbers.
 

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Discussion Starter · #15 ·
Just curious: Have you owned this car since new?



Compression / Leakdown tests
Boost leak test

See if there's a mechanical issue you need to address.

Oh, and I missed your one question. No, I didn't own it from new.

I got it used at roughly 89, 000 Miles from a Subaru Dealership.
 

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The numbers I read in your data logs lead me to a few observations. Unless something is wonky on my reader your throttle position never reaches 100, you have low boost pressure, and global timing pull.

This is all indicative of a continuous serious knock.

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There's either a high point in your timing map around 1.1g/rev and 3200rpm, or the knock sensor is picking up exhaust noise at this point, which is what happened to my car.

Use the "adjustments" on your AP to pull a couple degrees of timing from the map globally, and take a driving around log. If your still getting knock events at the same points, its a faulty reading, if the knock goes away, get a pro tune
 

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Discussion Starter · #18 ·
The numbers I read in your data logs lead me to a few observations. Unless something is wonky on my reader your throttle position never reaches 100, you have low boost pressure, and global timing pull.

This is all indicative of a continuous serious knock.

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Damn... I need to figure out what is causing this knock then.

I'm not sure if these leaks would be causing the knock or if it's the common three: fuel, carbon, spark plugs.

I hate that it's my daily.....:pray:
 

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Discussion Starter · #19 ·
There's either a high point in your timing map around 1.1g/rev and 3200rpm, or the knock sensor is picking up exhaust noise at this point, which is what happened to my car.

Use the "adjustments" on your AP to pull a couple degrees of timing from the map globally, and take a driving around log. If your still getting knock events at the same points, its a faulty reading, if the knock goes away, get a pro tune

Is that typical with a delete, though? I would assume that it would be more of an issue with a downpipe/Stage 2, or if I was straight piped..... Damn.

How many degrees do you think I should pull from the timing at these numbers?
 

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Damn... I need to figure out what is causing this knock then.

I'm not sure if these leaks would be causing the knock or if it's the common three: fuel, carbon, spark plugs.

I hate that it's my daily.....:pray:
I wouldn't write the engine off. I had some serious knock issues that were a combination of turbo inlet and tgv leaks. Completely solved mine.

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