[WheelinNdealin35]

What's up everyone, so I am new to tuning as well subarus but am always looking to learn more on any car related subject, so please my ignorance for the time being. I have done my best to search up the concern have, although I'm afraid I'm just not getting a direct answer through google. So decided to ask here instead.

Here goes. So I've got an 06 wrx and the car is tuned to stage 2 EBCS 91/92 octane MTv310 p2433 final delete tune with a cobb ap. Yesterday I noticed the FKL value spike to a quick 4.20 or so then it was recorded. After continous driving I noticed it would be at around - 1.40 around 2k to 3.3k rpms. After it would zero out, as well zero out during WOT. Then values of -.70 would show up around low loads and then shoot back up to -1.40 when giving it some gas. Eventually just went a surprised because hadn't spiked that much since I got this tune maybe a week and a half ago. Before this FKL was a very solid 0 but maybe it was just not picking anything up being since the retune.

Well I got curious and drove, did some pulls and i got Feedback of around -7.00 displayed very quick though, didn't even notice it until it stayed stored under the "realtime" value for lack of a better word. It zeroed out but remained stored is what I mean. I went WOT a few more times and data logged this. Only to find out feed back was sort of consistent now yet the values smaller maybe -1.45 to -4 iirc. I care alot about the car and hope its nothing serious or atleast knowing whats going on would ease my mind. It is my daily driver after all just don't know where to go from here. Any input is appreciated and thanks for reading me ramble on.

 

[RogueMantis]

The reason that the numbers go away quickly is because the ECU zeros out the feedback knock every time you change engine load levels. Is your DAM constantly at 1.0, or does it dip lower? You might also list any mods you have done/what type of tune you have (protune vs. OTS).

There are lots of things that can cause feedback knock, and not all of them are actual engine knock, so any additional information would be helpful.

 

[WheelinNdealin35]

Apologies for the late reply, been away from forum a couple days. Only mod(s) are

-an invidia tbe/bellmouth downpipe

-and custom tune which is a just a stage 2 91 oct
(Which i obtained)

My tuner assured me that this tune was more on the "conservative side" ( don't exactly know what that indicates). I imagine it's less taxing on the a/f mix..? Not sure. I can try to upload some logs if it helps, though i may have to trim them as they are long. Even more odd is that feed back knock has been climbing a bit , which doesn't me happy . From what Iv'e observed on the logs DAM remains at 1, bit confused though because there is another parameter that is titled Dynamic advanced and that one fluctuates . I was told that i have a loose heatshield but i already knew that pre current tune and even then i never had FBK , some instances of Fine Knock Learn. I hope isn't anything serious.

 

[WheelinNdealin35]

Also pre current tune I was running an ots stage 2 tune. Reason I ended up with my current tune is because when I had the ots tune I was getting a turbo waste gate solenoid out of range/performance. The new tune helped this issu but Im wondering if old issue is still maybe some underlying problem. Just my thought.

 

[RoboTuner]

You do know the EJ255 outflows the TD-4 they slapped on from the previous EJ205, right? This is a common issue w/ catless TBE, add an intake and it's worse.

You posted an EBCS, if it's not a 3-port then get one and retune for it, they control boost better than 2-port.

GET LOGS, the factory o2 sensor is junk in boost so grab an AEM Wideband, believe me it's worth every penny on a turbo car. There's ways to integrate it into the factory harness for logging on the AP but requires knowledge/splicing. W/out the logs (even factory o2) we can't help much more.