Intake manifold and throttle body bolts are torqued at 13ft/lbs. You want to start torqueing at the center bolts then crisscross you way out. The last bolts to be torque should be the ones on the outside of the manifold. You can watch this youtube video around the 14:30 minute mark:

 

Paul

So, I put the manifold and the rest back together.
I checked everything twice just in case and all good. One of the wire loom 🔩 bolt behind the manifold fallen down between the cylinder heads . 🤦‍♂️ Try used some telescopic magnet,but no luck,so it's stays there .
Before I started the engine I drained some engine oil,because I bought MMO and want to try.
so, engine started fine , no leaks and no issues ,but those tapping noise still there between 1200-1800rpm.

. Not as loud than before and not always able to listen but is still there. Anyway, at the moment I'm running with MMO mixed oil for a hundred miles and after that using engine flush and replace the oil and filter and let's see what happenes. To be fair, when I take off the valve cover, not seen black smudges, but dark brown mist on the parts..




Overall the engine is running much much smoother . Did a 20miles spin and no issues, no codes.
Partially I'm happy ,but the project not done yet.

Hope it's not valve stem!
I'm not sure because I don't have any missing oil between the 7.5k oil change and no oil residue end of the exhaust and steam smoke only the cold morning start

 

Good job Pushi. Question. Did you look at the valve stems of each cylinder when the manifold was off? If you do have a leaking valve stem seal, you should have seen oil and carbon on that particular valve set.

Sorry about the bolt. You can find it though. I always learn something new after the fact. Buy one of these. Less than $15.00 on ebay.

"Megapixels HD USB C Endoscope Type C Borescope Inspection Camera for Android"

If you have an apple phone then make sure it is Apple compatible. It is a very useful tool for looking inside your cylinder bores or under manifolds. If I would have thought about it before I pulled my intake, I would have known with absolute certainty what was wrong with my knock sensor before. Which really wouldn't have mattered in my case. But maybe it will help others. Good luck.

Paul

 

I looked into the intake valves and found a tiny bit oil above the valve ..you see there,those tiny bit oil shiny . No carbon built up on the valves and on the surrounding. Seems to me all clean and good condition. On those spark plug I found a tiny bit oilish dirt, but easy cleaned up. (But! If the valve seal doesn't do the job ,why not draining those tiny oil back to the chamber?? ) Or I'm wrong?

Anyway, looks like very soon I took the manifold off again because the coolant bypass pipe very tiny bit leaking... is not happened before 🤦‍♂️
Found it only today,when i checked the valve cover seals ..

 

Are all of your valves like that? Not good. Do you have any oil in the bottom of your manifold? That would indicate a bad PCV Valve. Oil sittin on top of the valve would "seem" to indicate valve seals. But is it really a bad valve seal or is there too much vacuum being built up inside the system because of a faulty PVC system? Or did you tilt the intake and some oil in the bottom ran into the port? Remember... These are just indicators. They don't mean much yet. Not until you have all of the pieces. But I know a new Lexus PCV Valve is not that expensive. And you should see what I just went through on the thread labeled "Another Tough Call" to see what I have done so far. I may have spent a lot of time and money to diagnose something I may have already fixed. But I didn't know that at the time. And to be perfectly honest, even though everything is looking good for me, I probably won't have piece of mind for a couple of weeks.

Paul

 

I had a oil mist surface inside the manifold and only just those 1 valve had oil in it.. the rest is clean and dry! Already fitted the new oem pcv valve . Something worth checking ,which is part of the pcv system ?

 

The hose on the passenger's side coming into the valve cover and the hose on the drivers side going from the Throttle body to the actual PCV valve which is plugged into the valve cover on the drivers side through a rubber grommet. Wish I could say for certain that it's not the valve guide/seal for that cylinder but I can't. I sincerely wish you luck though. You could try a good decarbon/engine flush like I just did in the "Another tough call" thread hoping that it's just some sludge causing a leak-by of oil through the valve seal for that cylinder.

Paul

 

I have to add of course that just because you have oil on that cylinder, it's just a symptom. Could it be a valve stem seal? Sure. But it could also be a stuck piston ring allowing oil to blow back up into the intake. Just making sure were clear here and another reason you may want to do a thorough chemical flush. Good luck Sir.

Paul

 

Thank you for all the shared information ! Appreciate that! 👍
I need to take off the mainfold again,because those coolant bypass pipe day by day getting worst and don't really want to loose the only 2 years old OEM red coolant when the pipe burst.
So the plan :
manifold off again , pick up the fallen bolt luckily, fit the new pcv valve ( bought a threaded one first accidentally -)

12204-50030

🤪 , fit the new bypass section with new gasket, checking the valve area (try using the endoscopic camera) , changing the rocker cover gasket ( while I'm there checking any worn issues (if have) ) and that's it really.
Than ill try those BG engine flush and additive and let's see what happens.

 

And he's FEARLESS! So, what happened to the coolant bypass hose? Is this something that happened due to pulling the intake? Is there anything here we can learn from? Thanks.

Paul

 

That particular hose that has the leak did not need to be removed to take off the intake manifold. I actually attempted to remove it but i didn't have the tool to grab onto it so I let it be. I was able to remove the intake manifold despite not taking it off. I believe that is the heater hose.

 

Hey You! I haven't heard an "all done" from you. Are you all done? It now looks like my minor water leak after the dealer was an improper bleeding of the coolant. She seems to be fine now. :-)

Paul

 

Yes, its "all done" for me (fingers crossed) . Just finishing up some maintenance and monitoring for any leaks. The car drives smooth as ever and power is back! I was driving with the knock sensors offline and a snipped vacuum line for a while and it was literally in limp mode. It feels nice to be able to rev past over 2000 rpm again. Yes I did notice that coolant kept getting low on my car every few days after I drained and filled the radiator, it just needs to time to burp out all the air .

 

Hey Pushi, I looked at your picture again of the coolant discharge. I think that fitting is pressed into the crossover. There may be no fix for that other than a new crossover. Anyone else have any experience with that particular piece? Thanks.

Paul

 

Before I put the manifold back I installed a little fence to keep the riff raff out or at least make it a little harder for them.