Light rattle/knock on gentle acceleration

[What!?!]

With COVID lockdown in Sydney , I havent been able drive much .. today I took the car out and as I was accelerating from the lights at no more than 50% throttle, I heard a faint rattle /knocking noise at very regular interval about 2-3 per second until I eased off the throttle.

has anyone had similar? Any suggestions where to look? Petrol tank is half full (always use 98ron), and bought maybe 7 weeks ago at most, maybe it’s gone bad already?

 

[robo498]

Maybe you could top up with fresh petrol? See if that helps? I always find BP ULTIMATE works best with Subaru's!

 

[Lenny]

We've had the same problem for quite some time now. Light pinging then massive amounts of black smoke. We got to a Subaru specialist but not Subaru and I've ofetn wondered if there was an updated tune. We only run 98 and have even tried keeping the tank above half just incase it was a surge problem.

 

[Nzlevorg]

I believe my 2014 has started doing this and I think it is pre ignition or detonation. Haven’t got to trying to resolve it yet.

 

[Robsyuk]

We've had the same problem for quite some time now. Light pinging then massive amounts of black smoke. We got to a Subaru specialist but not Subaru and I've ofetn wondered if there was an updated tune. We only run 98 and have even tried keeping the tank above half just incase it was a surge problem.

BP is only 98ron, treat your car to some esso 99, momentume or shell v power and watch your car transform. That's if 99 in available in your country.

 

[Nzlevorg]

Incase you hadn’t sorted it - I put an “octane booster/cleaner” in the tank and filled up. Made a massive difference & removed the noise which makes me think the in tank fuel filter could be getting a bit dirty & also the injectors may need removed and cleaned but haven’t got round to getting that done yet. Also unsure if i can buy a seperate filter for the pump or have to buy the whole pump.

 

[Robsyuk]

Incase you hadn’t sorted it - I put an “octane booster/cleaner” in the tank and filled up. Made a massive difference & removed the noise which makes me think the in tank fuel filter could be getting a bit dirty & also the injectors may need removed and cleaned but haven’t got round to getting that done yet. Also unsure if i can buy a seperate filter for the pump or have to buy the whole pump.

I wonder if the in tank filter should be replaced after x miles.