OK Guys, seems something was FIXED on last weekend, and now, when engine is warm, so I start the engine and let it idle and the AFR won't drop to 16.0!!!
well, it will drop to around 15.x or almost 16, but then it will back to around 14.7 at around 5 seconds!!!
OK, let me share what were done during last weekend:
- Changed another used AFM(originally, 1st AFM has lean idle issue, then change to 2nd AFM, same lean idle issue, now, last weekend change to the 3rd AFM)
- Changed from Ultra Silicone Spark Plug Wire 7mm(was bought brand new from Japan) to brand new NGK Power Cable
- Changed new spark plug NGK BKR7EIX-P
- Changed new oil catch tank, and also connected back to intake hose, so in "closed loop". Becasue the old oil catch tank was vent to atmosphere, and the intake hose side was plugged so no vacuum leak
- Ultrasonic cleaned all injectors. Note, before and after clean, flow rate is almost the same, no big difference, so maybe not dirty? Or maybe due to only using Shell V-Power in 10 yrs? Also, the injectors are around 200cc/min, it seems wired so I put this question in another thread(
https://www.clubvr4.com/forum/showth...flow-rate-size)
Sorry that I changed all these together and didn't know which was the root cause.
Anyway, I will keep watching the result in these few weeks, and update you guys.