So I have some problem with my engine - it is losing torque/power over time - mostly under 3k rpm.
When I accelerate lets say at 2.5k rpm (not neccessary full throttle, it could be 2/3) it is accelerating like it was on hand brake or like something was blocking exhaust - very poor (lazy) gas pedal reaction, no power, different noise like something was blocking it.

Then when it pas 3k rpm it is kinda normal - maybe not ideal little bit less power but not that much like under 3k rpm.

And then when I disconnect battery the car is like +50NM and +50HP under 3000rpm.
Very sharp gas pedal reaction and instant acceleration even at 2500rpm. Different engine sound also.

What I did:
cleaned maf, map sensor
cleaned throttle body
new spark plugs
added something to fuel to clean fuel system
air filter is new also
checked vpower racing fuel but the same effect

But it did kinda nothing. It is not the same every time sometimes its better, sometimes it is worse but far from the state when i reset ecu (disconnect battery)

Disconnecting battery helps for 150-200km - the torque and power is there under 3k rpm. But then it is changing - mostly felt under 3k rpm...

Any ideas?
Forscan shows no error codes.
Thanx for help.

 

1st thing should of been a diagnostic code scan, followed by assessment of short & long term fuel trims, along with air/fuel sensor & O2 sensor monitoring.

 

there are no error codes, I will log some ride with forscan later and put it here, thanks

 

so I dont know it this will tell you something? today also was better day, not that much of a lag bo still after disconnecting battery much inprovement betwen 1800-3000rpm, this is before

 

Not really telling me much. Long Term fuel trim is a bit high, but not massively.

I'm used to Mazda's MMDS (IDS) display which shows actual figures, rather than just a min & max scale. Also I need to operate the throttle & watch the reactions . Its hard not having the car in front of me.

Can you bring up both the Air fuel ( A/F ) & O2 sensors, along with RPM, give it a 2 - 2500 quick rev while recording? A/F sensor maybe called O2 bank 1 sensor 1,

 

just rev it on idle? or accelerate on some gear? I will do it just have to wait until it "broke/readapts" itself cause I reseted the ecu yesterday.

 

Rev it from idle in neutral.