When datalogging my car, if i start a 3rd gear run below 2950rpm i get large counts of knock that follow through to the end of the run. However, if I start the run at 3000rpm or higher, I get a clean run with little to no knock.



Yes, i have increased the Knock Vs RPM table.

Yes i have made sure NOTHING in the engine bay is rubbing.


Any other suggestions? Anyone have something like this before?

 

possiby too much timing in that region of the map...

 

i have the same problem, except for my counts of knock is a bunch of 1's in a row and the occasional 2 at the start of the log. im running the stock timing from 0-180 load. usually when i start from 2600 or less. so if anyone has any suggestions i would like to know as well. i am running stock downpipe and stock catback so i dont know what could be causing the knock.

 

I'd suggest looking into jcsbanks knock control stuff. Put in a bit of high octane fuel (race gas) and go out and see if you've got the same phantom knock. If it's the same basic stuff, you can start to up the load threshold values in the knock table. There's also a few multipliers to play with. I had similar problems as to what you're describing, and it only took small changes in those tables to make it go away.

If the race gas makes it go away then it was probably real knock and you need to pull timing (or add fuel if it's lean) once you're back on regular pump gas.

https://www.evolutionm.net/forums/ec...ble-found.html

Good luck.

 

I fixed my problem (so far) by increasing the low and mid "knock multiplier" values as per that thread.

 

It would be wise to verify that you are not seeing real 'knock.'

 

It was phantom knock, even with extreme Timing reductions and the addition of 110 octane the car still displayed knock in that area.

With the changing of the knock multipliers the car has ran perfect for a week or so now, including a few passes down the strip at 112mph

 

Your solution by raising the knock multipliers helpd me too. I also realized that timing was a little jumpy in the lower RPM. Smoothing it helped a ton.

 

Can ecuflash show knock by flashing the CEL?

 

^ you would have to get a tephra modded rom and transfer your settings in there.

 

Stealth, what rom are you using? I had an issue with low rpm knock on a car running the 5.10 tephra patched 94170015 rom. I tried to tune it out by lowering timing and adding fuel. No go. Started going through the tables and found that the Idle Stepper Table had the TPS scale jacked up. Once I fixed the TPS scale and put all the changed cells in the timing and fuel table back to what they were originally, found that there is no knock. I didn't need to mess with the knock tables on this car. I also re-downloaded the Tephra 5.10 patched Rom again and found that the values there are messed up as well. So I can only assume that the knock issue is inherent to the 5.10 rom's idle table screw up.

 

Knock is more likely at lower RPMS as the air mix has more time to be ignited...

Scorke