Sale ends todayGet 30% off any course (excluding packages)
Ends in --- --- ---
Forum Posts
Courses
Blog
Tech Articles
Hi all,
Using COBB on Mazdaspeed3 (MPS), cruising conditions after engine has warmed up would show a constant high count of knock retard. From what I understand, this is intended OEM behaviour to save fuel (advance ignition to limit at low-mid load).
I have been experiencing an inconsistent response to my throttle (how power comes on) and I believe it is related to how quickly the ECU allows the KR to "decay" under load.
Example scenarios:
1. Stab the throttle from low RPM (High delta TPS), car takes off like a rocket, no KR reported.
2. Cruising where KR is active (low load), stab the throttle, very poor response and sometimes minor buckle.
2a. Cruising KR is active (low load), let off throttle (0% TPS, KR instantly disappears), Stab throttle, Car takes off like a rocket.
Key to mention here: KR under full load was the second thing I tuned for (from the OTS map) after a MAF calibration.
Any suggestions appreciated! :D
Update:
Logged good/bad conditions back to back and it looks like the numbers don't lie.
Looking under a specific load (@WOT) and RPM (~4.5k) the ignition timing is about 3deg. But when KR is active @ 3 counts, it is at about -1deg. In addition AFR reflects the WOT (Knocking) map.
In any case, it is pretty annoying and I can't imagine this is how the vehicle was tuned from factory, so I will continue tinkering.
