TurtleRA

iTrader: (1)

So was logging my car as usual, and today this showed up in one of my logs. This is 100% stock rom. I might have a 2 count every now and then, but have never seen anything like this. I am in 5th gear I think during this. Just wondering if this is some sort of crazy anomaly, or something to be worried about.

richardjh

Just wondering what your RA's current fuel diet is...

Rich

TurtleRA

iTrader: (1)

94 Octane, same stuff i've been running for awhile. I think a hamster went through the engine. I did just have my oil changed, god knows what the technician dropped in with the oil.....maybe some pennies, a spanner.

boosted91t

iTrader: (65)

false knock, vibration from something??

richardjh

5th gear, throttle at 25 degrees, 2600rpm, touching 8.5psi (textbook commuter driving).

94 octane fuel... tick.

knocksum of 28.


That is indeed crazy.


There have been two times I've seen ks like that in my logs, and both times it was because of my bad fuel tuning - too lean. Yes, I still cry when I remember it!

Now IIRC, some stock ROMs have low-rpm "open loop" load points around 135-140, don't they? Check your open-loop tables, and see if it's possible you were hovering just below the cusp of open-loop load by using light throttle in 5th at 2500rpm.

Could it be the stock tune can serve up AFR 14.7:1 at 8.5psi (140 load) at 2600rpm?


Either that, or I'd be crawling around the engine/exhaust, looking for something metal rattling against something else metal!

Rich

omegis

iTrader: (2)

^This reminds me of this:
FPR Hose Zip-tie

May be fine, but I'd still check it out to be safe.

TurtleRA

iTrader: (1)

Looked at the stock rom, looks like in open loop 2500-3000rpm, load is 140. As for the zip tie, did that long ago. Good news is I flashed to the gst basemap this afternoon and in my 30 min drive I only had 2 counts of knock. Going to chalk this one up as an anomaly, however will keep logging to make sure it does not happen again. Heck even when I bounced off the rev limiter going WOT I only hit 10, and car was loud as hell when it happened. When this happened I heard nothing, just driving home like I usually do. That is why it disturbed me when I saw this when reviewing my logs. Guess tomorrow I better look through engine bay for any spare tools the mitsu tech left behind during the oil change.

richardjh

Well, I reckon it's the stock open-loop settings at work here. You were right on that borderline around 140 load at 2600rpm.

Your LOGGED load was 140-141. Consider that there are several different "load" values used through the ROM. Baro corrected, Baro+Temp corrected, etc. The one used for the closed vs. open decision could well have been at 139.

If that were the case, wouldn't that mean 14.7:1 mixtures at 8.0psi to 8.5psi...

Rich

TurtleRA

iTrader: (1)

Well here is to hoping this does not happen with the gst map. Just seems crazy that a stock map would do something like that, with knock going that high. I get worried seeing a 4, let alone a 28. It is too bad my WB is not plugged in at the moment, would of be interesting to see the AFR.

richardjh

Yes, those stock tunes with open-load at 135/140 load... it's way too high.

I've lowered mine - and Aus 2009 tune was never that high to begin with. I'm now using table values recommended by Golden.

Rich

sstevojr

iTrader: (7)

I saw ks like this once (only, thank god) back when I was stock. I was driving up a very steep grade in 5th gear and could actually hear the engine pinging like an old chevy pick-up. Reviewed the log and hit 28

richardjh

TurtleRA, compare the "Open Loop Load High Octane #1" table between your stock ROM and Bryan's v27. Bryan's dropped that 2500rpm area down from 140 to 120.

You might have just found out why!

Rich

richardjh

Snap...




The above was over a year ago... My RA on STOCK TUNE with nothing but mode23 enabled... driving in the hills, dumb AUTO mode... 98RON fuel... mild weather, etc.



...but you win on points! Highest knocksum on that drive for me was 7.

Rich

TurtleRA

iTrader: (1)

Here is my screenshot.....i'm almost becoming as good as you Rich at these screenshots. I compared v17 to v18 and 17 has the same as stock, so glad it is now changed. I am thinking we need to start a '28 club', however it looks like you need to be stock to get knock that high.