It is not just experience as experience will tell you look for likely source [based on failure rate].

In reality you need to witness play in two different members. With the weight on ground, it is hard to witness the play/movement. Suspension shops have more than the two post lifts and they can shift the weight on different suspension members. With long pry bars they can reach decisive conclusions. As DIYers we are at a disadvantage. As I alluded before, pay someone with the right equipment to diagnose and then put in your labor/time.

The other thing the experience tells/taught is replacing the other side/pair when one member has the play as the life expectancy of the other member would be over too.

Salim

 

Haha, very interesting analogy. I have to use Google translator to understand it properly...

 

Just an update about what I did today. First I did a DIY smoke test, no leakage was found. I am confident with this result. I also replaced a MAF sensor bought from Amazon. The off-engine reading is 0.32 g/s which is close to the standard value （the old one is 0.2 g/s). When I run the engine, at idle, the LT trim is around +10% and ST trim is 0% which is in the normal range. However, when I rev up the engine to 2000 rpm or 3000 rpm, the LT trim would be +20 to +30 % and the ST trim is 0%. This still triggered the fault code. Have no idea what the problem is now. But I don't very trust this MAF sensor. Probably I am gonna buy a Denso or Duralast product, which is more than $100.

 

Genuine Denso sensors are the only way to go. Anything else is a crapshoot.

 

Thanks! You are right! After I replaced it with a Denso MAF sensor I bought from ebay. The fuel trims become normal. I think this problem has been solved.