thanks, appreciate it
definitely can, been using 5w40 for a long time. Didnt the service booklet recommend 20w50 for our Persona instead 

brake disc warped.
You bought a lemon? how come so many problem? gen2/persona should be reliable and less problem at relative low mileage.

Err.. I don't really have anything that's systematically arranged.

So far all my cryptic issues are electronics problem:

-Check Engine Light with knock sensor voltage too low probably due to I tried heel-toe downshiftbon my car.. Once i drive like an Ah Pek then the code won't come back, after clear error code.

-If your oxygen sensor failed: You go to spare part shop they'll give you black color Gen2 O2 sensor. That's not the right one. Insist O2 sensor with green cable. Otherwise you going to be like me who bought 3 black O2 sensor until I gave up and send my car back to Proton Edar.

-Most of the unexplained electronics problem occurs when car battery about to die. If you got strange problem that your wireman cannot diagnose, at the same time battery due to be changed already, you can always try new battery when all method exhausted.

Engine bay there basically nothing much. Just make sure you maintain according to schedule lo... Use distilled water for coolant mix, use original timing belt assembly (zordaq keep on highlight this in their FB page), change water pump at alternate timing belt change, solve crankcase cover gasket oil leak by replacing the gasket with silicone punya, etc etc.

Getting a OBD2 Bluetooth reader is a good investment. I got one Scantool.net bluetooth version in my drive so that I know what's the CEL for..

I'm using this:
https://www.scantool.net/obdlink-lxbt/

You'll need app in your phone to link to your ECU.

The port is behind of your engine bonnet open switch.

Nope. Just plug, pair Bluetooth with your phone, then launch app. This brand got auto sleep function. So you can leave it in car.

If you're hesitating you always can buy the cheap one from eBay to try out first. Last time i bought 3, only 1 worked, but the the one worked spoiled in 2 weeks also. 1.99 usd each only.

Edit: Upload photos.

Coolant reservoir i actually use distilled water. The level just high enough to submerge the pipe from radiator would do.

The rationale is reservoir tank under normal circumstances function as catchment area for expanded coolant during hot engine. When engine cool down, coolant volume will shrink and siphon back fluid from reservoir tank to make up the void.

Thus under ideal situation, it should contain same fluid as in your radiator. But if coolant tak cukup, distilled water also can.

On the proportion of coolant versus diluent, if you check those coolant imported from country with winter season, they actually indicate the more percentage coolant you use, the more resistant of radiator fluid to form ice.

Looking at Malaysia don't have winter, we don't really need 100% coolant. We only need it for anti-corrosive properties. So standard 50% mixture should suffice.

better use proton atf oil rm150++, outside use dexron which is long term damaging ur gearbox. use normal spark plug can last 50k km. i just refresh my car and now full tank with 50% highway and rest in kl city can go up to 560.10km.

they  sell one bottle i liter rm30++ so 5 bottle rm150++, unless u can get mitsubishi diaqueen that sell 5 liter.