bro mine nearing 15 years. still no oil consumption and using 5w30 till now.
could it be other problem?

bro better go and do proper diagnostic.

https://www.firestonecompleteautocare.com/b...-without-leaks/ , google may not be accurate.

You can start with finding another better mechanic. What this one spew was utter bullshit.

- Rev your engine and see if there is blue smoke coming out of your exhaust.
- Check your coolant if there is any oil mixed in it.
- Check for oil stains around your engine, especially around the valve cover gasket and cylinder head gasket.

Most likely you changed your oil always a little too late and have clogged up the piston ring's oil flow channel. Thus, your piston rings are fried. Most likely a top overhaul to replace new piston rings and seals are needed.

Toyota engines are prone to this issue. Change your oil early and don't stick to the 10k km for FS.

Those days, a top overhaul might cost around rm1.5k.

Now it may cost more due to inflation. Top overhaul is fairly easy as you only need to remove the engine head and replace worn parts at the top engine area.

Suggest you to get direct quotation from a few workshops to better guage the overall price + parts.

This is the consequences of not taking car of the car. The repair amount needed will be huge.

Dear ts, u prolong to 20k for oil change really messed up your engine. Whether the damage is already too much or not we do not know unless we test it.

If u dont want to spend any more money on it..u can put a bandage... Everytime pour in lucas oil stabilizer into your engine during new oil change.

Follow below steps if u want to save money + help your engine.
1. Go mechanic and do dry compression test for all your cylinders are good. If still good, proceed to step 2. If no good, u will have to do full engine overhaul because your cylinder walls already almost certain full of deep scratches and grooves. Full overhaul for damage like this includes rebore cylinder walls and putting in bigger newer pistons. Rm5k and above easily.

2. Take boroscope and look down into cylinder walls. If no deep scratchs on cylinder walls, proceed step 3

3. Buy engine flush or cleaners like marvel mystery oil, lucas complete engine treatment, etc. It is a aggresive cleaner. Follow the instructions. Not 100% but hopefully this will slowly clear the gunk around your pistons and free up all your rings and also oil passages that has been blocked. If oil consumption reduced, u can try again. If no reduce, go step 4.

4. Open up and pour marvel mystery oil directly into pistons through spark plug passage way. Wait few hours, manually turn the engine a bit, then pour again and wait another few hours. This way is very very aggresive in case step 3 does not work. See youtube to get what im saying or find a mechanic to help you.

... you mean sometimes 20k KM only change engine oil?

my current situation: 16 years old with 250k+ km and 13 years old with 440k+ km. both on 5w30 full syn, both engine is never done any overhaul before, both engine rev to before rev cut says few times in a week at least, oil consumption based on top up around on 5k km is between 0.5~1L.

my suggestions: check engine inside out and/or change foreman.