I am using Ecuflash and Evoscan, and understand the general concepts and the timing/fuel tables, and have a couple of questions for you guys. BTW, I'm on Tephra v7.
I logged my car and found that I had some 3 counts of knock here and there and fixed them by retarding timing by 1 degree in the timing map.
Next I found there are also counts of 2 knocks in many other places in the logs (not at wot, just normal spirited driving).

1. Should I be concerned about these counts of 2 knocks and try to fix them, or leave it alone, and only focus on the knocksum >= 3?
2. Someone told me you can add more fuel to fix knock, instead of retarding timing. But in my case, this knock is not at WOT, and it's at lower load cells, most are between 80-160 load, which in the fuel map, it's inside to upper left quarter, which are all 14.7. Not sure if it makes sense to change the fuel table instead of the timing table to get rid of the knock.

Thanks.

 

Following this with some interest. I have the same issue

Do three 2000 to 7000 WOT runs and have no knock, but then drive home from my "test" area and get multiple 1 counts of knock at 2500rpm with 40 to 80 load. Can't seem to stop this even with timing adjustments. Was thinking maybe it was my Exedy clutch (sports organic) or maybe a false knock count from hitting cats eyes or road imperfections. ?

 

Fireescape, from what I've read on this forum, you can also try to run higher octane fuel and see if the knock goes away. If it does not, then it's phantom knock. You could adjust (increase by a few points) the knock background noise multiplier table at the 2500 rpm to see if it goes away.

So the question is, do counts of 2 or 1 need to be fixed in the tune or just ignore them because they are not significant enough to produce any damage?

 

Try a REAL boost leak test. With soapy water and a big enough air tank.

I had this knock problem a while back, found I had three very minor boost leaks.
Throttle body shaft and output pipe gasket. The knock counts would go to 12 every so often.

Good luck. Btw 3 counts isn't that bad as it is only 1degree

 

RE 1 : Should you be concerned? Not really, but you can still try to fix it. Try removing more timing (like 3 degrees) in the affected areas and MAKE SURE the area around there is as smooth as possible. If the knock persists I would return the the timing values you have now, smooth it out if possible, and not worry about it. If it only happens occasionnaly and not every time you cross that rpm/load point it's unlikely it'll cause any problems.
RE 2 : Depends what the current AFR is. Running too rich can also induce knock. Knock in that transition area (80-160 load) can be caused by the map not being smooth enough; see if you can get it any smoother and it may get better.

Is it a long string of 1 counts or just for 1 or 2 rows that you get the 1 count? If the latter I wouldn't worry about it. If the former and you've already tried timing adjustments, I wouldn't worry about it much either.

 

Thanks Raptord,
In my case I see long strings of 2's, maybe 6-8 or more consecutive rows in the log. My timing map is pretty smooth, I think it's just a bit high in some spots where I see 2's. That's why I wanted to know if knocksum 2 should be fixed, or ignored.

 

the KNOCKSUM hits 2, and stays there for a little before it decays.

So the number of rows it is there, is, to the best of my knowledge, mostly irrelevant?


Feel free to correct me if I misunderstand I am also new to this.

 

I'm talking about smoothing the timing map. Try making a more drastic change, up to 4 or 5 degrees. Smooth everything around that area. If the knock persists I wouldn't worry about it much. The last step would be to try race gas and see if it's still there.

If I see a 1 or 2 pop up for only 1 row in a log, I'll ignore it. If it appears and stays for a few rows before starting to decay, then I'll try to adjust the tune to get rid of it.

 

thanks for the advice. i need to go back and fix those 2's then since they are staying on for many rows.

 

Thanks for your ideas. I'm already using the highest octane fuel (98ron = 93 us fuel) that i can get, maybe I can use a octane booster? Ill try something like that and see how things go.

 

Octane booster doesn't raise the octane enough for it to be reliable for this sort of testing. Have you tried checking for a few liters of race gas?

 

I'll have to have a look around for some elf102 or something. There is a race track about an hour from home, might be able to buy 10 litres. For racing use only of course! Cheers

 

Double check any knock if you are not @100TPS, it can be fake too...
Post a log if you want precise tips.
Cheers.