LightRobin

Ah right, I don't think its an issue of aftermarket parts since it only started making the noise about 5-10km after I did an oil change on it, that combined with it only happens when the engine is warm, could have something to do with the variable valve timing, maybe the computer changes the timing a bit as the engine warms up, as for the people with scanners there seem to be 2 of them 30mins away from me so I might see if they want to take a look

Yeah I'll change the spark plugs anyway, the throttle body had a bit of carbon buildup in it but nothing major, haven't talked a look at the maf and a better scan tool would be pretty expensive, especially one with live data so I don't think I'll invest in one quite yet

Its a 3 cyl engine 🙃, I haven't tried swapping the sides over but I have unplugged them one by one, the sound happened less frequently and quieter when I unplugged the injector closest to the timing belt side of the engine, although it didn't make the sound go away completely so I don't think it's related to the injector/ignition on that cylinder, might swap out the spark plugs regardless and I'll need to take a look at the belt for the squeeking but probably won't get around to anything till Sunday so I'll update then

And yes I took the filter out of the box, it looked like it had been changed recently

Also I had a look at the repair manual and the alternator belt has no tensioner and doesn't run around any pulleys, just the alternator to the crank pulley so I doubt it's related

Just watched the video back, all those sounds were from my car actually

I've inspected the air filter and spark plugs and they both looked fine so I don't think that they're the culprit, the sound is much louder in person and barely comes across on the video, best I can describe it is it's a metallic tinny knock, almost as if you were to tap a screwdriver on a piece of sheet metal, I will do some further poking around tomorrow and will try to get a better video of it Fyi some of the sounds you were hearing could have been other cars since I filmed it in a busy parking lot

Knocking noise is definitely from the engine, best I can tell is it's coming from the timing belt side of the engine, not far enough over to be the engine mounts but in that general area. The scan tool I have is just one of those basic Bluetooth ones that just show codes so can't check live data, I'm working all day today but will try run it without the belt tomorrow, tried to take a video of it rq, https://youtube.com/shorts/Jlxf2Q3i1f4?feature=share let me know if you hear it, it's the best I can do for now since I'm at work

So it's been a while but thought Id update anyway, I took the oil pan off yesterday and the bottom end looked immaculate, couldn't have been cleaner, nevertheless I replaced the rod bearings since everything was already apart, engine sounds exactly the same as before so that rules out bearings, plus I've driven about another 3000km since last update and the sound hasn't gotten any worse so I'm really confused now. The accessory belt has start to squeek when the engine is cold but goes away when warm, not sure if it's related and possibly the belt tensioner is making noise? It baffles me that it only happens when the engine is warm, surely a tensioner would make noise regardless. But anyway, anyone got any ideas what else it could be?

Just a quick update, I got my hands dirty and took a look at the following: Unplugged injectors to see if the knock changed at all, it appeared to quieten when I removed cylinder 1's injector and stay the same for the others Took the spark plugs out, they had oil in the plug wells and on the threads but the tips were dry, it wasn't flooded with oil but almost enough to drip, possibly piston rings gone with piston slap making noise? It doesn't burn oil as far as I can tell and there's no smoke from the exhaust We also tried sticking a rod down each cylinder and the rotating the crank till the piston was going down, then tried pressing on it to see if there was play in the bearing allowing it to move, nothing moved as far as I can tell, also inspected the timing chain and pulleys, everything looked in good condition. One thing to note is that when we looked down the spark plugs holes with a flashlight there was a fairly thick black coating on the pistons, carbon presumably but not sure if it's normal so thought I'd mention, anyway I may order some stock size rod bearings and try to change them from under the oil pan, will update with how that goes if I do although if it needs new piston rings too it will be a waste of time Ps. Noise appears to start at 65c oil temp and worsen as it gets warmer, perhaps we felt no play in the pistons because the engine had cooled too much (I warmed it up before taking things apart)

Ahahah ye, just baffles me as to how it made no noise before the oil change, then after the oil change I drove maybe 10 kms and it started knocking, perhaps the clean oil washed away some sludge that was cushioning the knock?, Anyways it's as you say, I'll either drive it till it blows up or try to trade it in to an unsuspecting garage if I find a replacement, whichever comes first, it's pretty hard to not rev high with such a small engine, it'll struggle to keep up with traffic haha

Just to add to that, it just clicked that the vibration I feel in the clutch would point to something knocking on the crankshaft, since the clutch is directly attached to it, it is a quite sharp vibration too, any ideas if it would be worth dropping the oil pan and checking for play in the rod bearings? It only makes noise when it's warm so it would be difficult to drain the oil and drop to oil pan while it's still warm enough to have play

The car had sat for about 6 months before I bought it, the previous owner was a girl in around her 20's who had moved to live in another country and told her dad to sell her car, she wasn't the first owner of the car so maybe the owner before her did some higher mileage journeys, the car had an oil service sticker on the windshield when I bought it that said the next oil change was due for 161,000km or February 2021, I changed it at the start of July so a few months overdue but I don't think it would've affected much, the oil looked clean when It came out nevertheless and didn't have any debris/sludge, the mechanics all opened the bonnet and took a listen as I revved it, (they were all from different shops too), they all agreed it was something inside the engine and they'd need to take it apart to see what exactly, I can feel a vibration in the clutch pedal with each knock so I dont think it's a head gasket but rather some metal to metal contact inside the engine, it's strange though because I'd expect rod knock to get quieter with thicker oil but it hasnt

Yes, 156,000 kms Put in castrol GTX ultra clean with the correct WV rating (502 00) Noise is definitely coming from the engine, went around today asking mechanics to take a look, 3 of them said it sounded like bottom end bearings/ I'd need a new engine Scan tool showed no codes We checked air filter and spark plugs when we changed the oil, both were good Bought the car from the city so I'd assume it was mostly city miles It's sounding like a new engine for me anyway, will probably drive it till it ****s the bed and look for a new car in the meantime, still confused about how an oil change would have scrapped the bottom end tho

Hi, I have a 2015 skoda fabia mk3, 1.0L 60hp mpi engine, I changed my oil a few weeks back and when I changed it the engine began making a knocking noise, more recently it has started making a rattling on and off while at idle, after all I've tried I've run out of ideas, any ideas what it could be? Fyi, Its got 156000km on it and I've owned it since April 2021, it had 151000km when I bought it. Observations: Doesn't feel like it's lost power. Noise only happens when rpms are climbing, stops once rpms are held constant and nothing when they're dropping. Noise stops above about 3k rpm. Noise only happens when engine is warm and gets louder the warmer it gets. Engine oil temp stays at 80-90 when warm Runs like a clock when it's cold What I've tried so far: Originally put 5w30 oil in but recently changed it to 10w40 which didn't change the sound at all, no louder, no quieter. Tried oil additive in with the 5w30 which changed nothing. Tried premium fuel to check for pre-ignition Pressed clutch in to confirm it's not gearbox noise. Held rpms at 3-4k for a few minutes to check for collapsed lifters.