Spark knock on initial takeoff

[Snake31]

I notice a little spark knock upon taking off with light acceleration on the first take off from cold start up. I usually idle for one minute before taking off. Engine doesn't do this after a couple start/stops. Does anyone else experience this on their M56x?

[Debonair]

Yup. I usually hear it in the afternoon when leaving work. I have to drive up a hill to get to the freeway and on occasion hear some detonation heading up it. I figured it might be spark plugs since I am just about due for them so I pulled a couple out to inspect. They are in great shape with no abnormal wear or corrosion. So...whats causing it?

[DFW2011M56S]

I think it is just the nature of our ECU and the adaptive spark timing control in place. I get it on 93 octane. Even blipping the throttle in neutral I sometimes have spark knock.

[ArmedAviator]

I think that's actually the VVEL system doing it's thing without warmed up oil. It makes quite a racket.

[Ilya]

Yup. I usually hear it in the afternoon when leaving work. I have to drive up a hill to get to the freeway and on occasion hear some detonation heading up it. I figured it might be spark plugs since I am just about due for them so I pulled a couple out to inspect. They are in great shape with no abnormal wear or corrosion. So...whats causing it?

How many miles you at again? I'm at 98,5xx and have been thinking I need to change mine soon cause I also started to hear this more since like 80kmi or so. I run only 93 and have since I got the car with 42kmi and usually run a gas cleaner, etc. every 5-6kmi.

[ArmedAviator]

I changed my plugs less than 1k miles ago. No difference in removing this sound (or anything else really), FWIW.

[Debonair]

Yup. I usually hear it in the afternoon when leaving work. I have to drive up a hill to get to the freeway and on occasion hear some detonation heading up it. I figured it might be spark plugs since I am just about due for them so I pulled a couple out to inspect. They are in great shape with no abnormal wear or corrosion. So...whats causing it?

How many miles you at again? I'm at 98,5xx and have been thinking I need to change mine soon cause I also started to hear this more since like 80kmi or so. I run only 93 and have since I got the car with 42kmi and usually run a gas cleaner, etc. every 5-6kmi.

94250 as of 5 minutes ago.

[Ilya]

How many miles you at again? I'm at 98,5xx and have been thinking I need to change mine soon cause I also started to hear this more since like 80kmi or so. I run only 93 and have since I got the car with 42kmi and usually run a gas cleaner, etc. every 5-6kmi.

94250 as of 5 minutes ago.

Interesting. I ordered mine and will probably just swap them out anyway...probably won't have the car at 200kmi so this is one time job lol.