Knock count at startup or low rpm mostly on cylinder four?

[kadireren]

Hi,
I have only custom intercooler and the other parts are stock. my vehicle is 1.5t sport touring hatch cvt. ıt is on 16.5/21psi. I did some maf scaling to correct my afr and fuel trims. They are ok now. I don't know if it is related to my maf scaling but now ı am getting some random misfires mostly on cyclinder four. They are at startup or low rpm such as 1250rpm and low maf voltage 1.25- 1.35 or 1.40v. the number of counts are not that much but it is annoying. How can I get rid of them? or is there a problem with my settings?

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[gtman]

I can tell you without looking at the datalog that a handful of "knocks" is very normal. Those cylinder events the misfire monitor sees happen all the time. The only time to worry is if you see a large amount in a very small time frame (100 in a minute, for example).

Concentrate more on important areas like fuel trims and knock control.

 

[kadireren]

I can tell you without looking at the datalog that a handful of "knocks" is very normal. Those cylinder events the misfire monitor sees happen all the time. The only time to worry is if you see a large amount in a very small time frame (100 in a minute, for example).

Concentrate more on important areas like fuel trims and knock control.

I just wonder why these misfires happens generally on cylinder four..

 

[gtman]

As far as why mostly cylinder 4, Derek Robinson explains it this way...

"Knock Count is a reflection of the ECU's misfire monitor. It is NOT an accurate reflection of anything other than misfire events. When will you see these normally? Startup, rapid throttle closures, rapid throttle inputs, rapid release of the clutch pedal, and sometimes at idle (especially if you have a lighter flywheel/clutch combo, and/or plugs that have been gapped down to prevent spark blowout at high load). A completely stock car, operating perfectly will still accumulate these counts. In my experience with these engines, you will see more activity on cylinder four compared to others, as the crank position sensor is physically located closest to there on the block. This usually isn't a concern area unless you see a steep count in a very, very short time (like 50+ in a few seconds), which will likely trip a P0300-variant DTC code."

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