Guys help please . It started after my change-oil and replacement of clutch fan. I dont know if these could have anything to do with it but I doubt if they really do.

To summarize it, the engine tends to die while im cruising, habang nakaapak ako sa accelerator. Yung tipong naubusan ka ng gas. And when I step on the clutch and let it idle, namamatay na sya ng tuluyan. When i restart it, hindi muna sya magsa-start, it seems that it's not getting any fuel kahit tapakan ko pa ang accelerator. But after 3 attempts to start, balik tu normal ulit. Then I could cruise normally again as if nothing happened, and I wouldn't know kung kelan na naman sya magkakaganun.

So far these are the things I noticed:

1. It usually occurs pag medyo malamig pa ang engine
2. Its weird but tuwing late afternoon lang or gabi nagkakaganun, it must have something to do with electrical consumption ng sasakyan
3. It cant be a low in fuel problem coz I always drive in full tank
4. when i tried revving it up while naka-idle, hindi naman nabibilaukan
5. during cold start, hindi namamatay ang engine on warm-up. dun na sya namamatay pag tumatakbo na ang sasakyan

My ride is a Nissan Vanette. I would really appreciate if you could shed some light, wala talaga akong idea. I'm hesitant na patingnan sa mechanic coz the problem might not show up