up to 5 degrees of kr but goes away with ecu reset

[jebsmith]

Well you guys are the experts so I thought I would post my question here also, thanks in advance too

So recently, with out changing the tune, or any moving part i started developing knock on my stock tune and my race tune. I did the normal checks

1. Plugs, all good
2. Compression test, all good 145 on 1, 3, and 4, 139 on 2
3. Leakdown test, less than 5% loss on all cylinders.
4. Sea foamed the intake mani, and fuel injector cleaner in tank
5. Ohm checked the fuel injectors, 2.3 ohms across the board.

Knock was still there.

Hard reset on the ECU.... ALL knock gone, stock and race tune.
Today knock came back, another hard reset and its gone again.
Do I have a bad ECU? How do I test this theory? I guess I need a spare ECU?

[Terminator2]

Need to see a data log. MAF could be off which will cause lots of KR but once you reset the ECM and the car is in open loop the knock will stop until the car goes back into closed loop ( normally 4-5 minutes after a reflash or VCM reset).

[brandonc]

What engine do you have? LNF?

Also, what octane gas are you running? Did you fill up at the same place?

[cobaltssoverbooster]

if cylinder 4 knocks the most try looking to see if it happens when you shift. if thats the case its ghost kr cause by clutch noise

[gn2beatu]

How recent is recently when your reffering to the NEW knock issues. Could it be a bad tank of gas, or a new gas station?

[SIXXER]

does the knock sensor go through a learning stage every time you reset the ecu?

[Iam Broke]

Yes, but I always logged more KR in the first 5 miles after a flash on the LNF, then it calmed down. Never reappeared later on unless there was a legit reason.

[SIXXER]

so does anyone know how exactly the knock sensor relearn after ecu reset?