1.6 FSI knocking when warm

[Itfharrys]

I’ve got a 1.6 FSI with 84,000 miles. I’ve owned the car for around 2 months and have noticed a knocking sound only when the car is warm. It’s most apparent at low rpm high load. I’ve recently done a full service with genuine VW parts and premium oil. The more I drive the car. The worse the knocking! You can really hear it if you’re setting off in 1st and don’t apply enough throttle- it’s really loud! Any ideas

[tditaff]

Some more details would be helpful. Is there a specific cause, does the knocking frequency increase with engine revs or speed of the car?
Any other symptoms or info?

[Itfharrys]

Some more details would be helpful. Is there a specific cause, does the knocking frequency increase with engine revs or speed of the car?
Any other symptoms or info?

The frequency is always the same and doesn’t seem to change with rpm. If I’m doing 40 in 4th gear - trying to accelerate it will cause this knocking sound. Also when starting on a hill, it will knock in first. Once I’ve surpassed 3k rpm it’ll quiet down. There is no specific gear, it seems to happen most in 3/4/5/6 when the engine is under more load. The warmer the engine, the louder the knock. I do have a ticking on idle when tie car is on idle. I’m pretty sure the timing chain is okay as on a cold start it’s very quiet and doesn’t rattle.


Sent from my iPhone using Tapatalk

[Crasher]

That sounds like actual “knock” or pre ignition and I had this once before on a 1.6 FSI BLG code engine and it was blocked injectors. To start with we put in Shell V Power and Red Line SI-1 Fuel System & Fuel Injector Cleaner SI1 | eBay but the whole 100 gallon treatment in one tank and with a few miles the knock started to reduce so we gave the car back with another bottle of SI1 and instructions to do it again when empty but it never quite went away so we end up changing the injectors. A word of warning though, if this is “knock” then when it is happening it is incredibly destructive to the engines internals, it can overheat and seize a piston in seconds so do your best to a valid generating it. If you have suitable diagnostic equipment you would be able to view the “knock” in measuring blocks on a per cylinder basis as your engine has dual knock sensors and live data display in Measuring Blocks.