since is 1st gen myvi. Possibility can be from these, since you mentioned it's hard to start during the hot afternoon. Normally such issue wont related to the engine oil, ATF oil, all the coolant etc. It is rather more on mechanical parts that need to operates the moment you cranck your engine.

Suspected parts, from what i see lah bro.

1) Fuel Pump – If it has not been replaced for a long period, it is a likely cause, as weak pumps struggle to maintain fuel pressure when hot. (Estimated cost: RM400+ for OEM)

2) Starter Motor (Heat Soak) – With age, the starter’s brushes and solenoid wear out. This often results in normal cold starts but harder starts once the engine bay is heat-soaked. (Estimated-RM350–450 for replacement).

3) Crankshaft Position Sensor – Quite a common problem in older Myvi or some Proton Campro models like gen2 back then. Normally when hot, the sensor signal weakens, causing prolonged cranking before the engine fires up. (Estimated cost: RM300++).

Try to send to different mechanic for a diagnosis

This post has been edited by incredibless: Aug 23 2025, 03:24 PM