Hi guys! I had an engine tune up a few days ago. Also changed waterpump and pulleys on my w208 Clk 55 AMG with m113 engine . Before the service the pulleys was making very noisy sounds which we where able to fix but after that the engine was really quite haven’t driven the car for more than 10kms since the service then few days ago while warming up the car i heard this light knocking sound on the left side part of the engine . It sounds light tapping or knocking sound coming from the cylinder head or the coil area. My car has 100k kms on it and runs very strong . I’m just wondering what that noise it and what to do to fix it . Thank you very much

Could it be ticking from the purge valve? Very common and can be ignored.

If not, you may have a slightly sticky lifter. Liqui Moly products are very good - I have used their Hydraulic Valve Lifter Additive Treatment in the past.

thank you very much! We found out it’s a loose sparkplug wire. No more ticking sound. But honestly I’m interested with thr liqui Moly hydraulic lifter additive. Does it really work?

thank you very much

Yes it made a small difference for me. Overall condition of my engine is good and it has a history of timely/frequent oil changes all its life. If some of those oil change intervals had been longer I think the product would have shown a bigger improvement.

My experience with the LM products more broadly is that they make at least a small improvement. But because the cost is so low (compared to labour and parts) they are generally worth trying.

how many do we need to put in our engine? I mean the liqui moly hydraulic lifter additive?

thank you very much

I used one bottle, but the used two.