My friend gets a 2003 Acura MDX, and recently he hears noises coming from the driving belt, we suspect it is the problem with the driving belt and I think it could be tensioner pulley

Here is the driving belt diagram:

Knowledge preparation from a good source

My friend like Eric’s video, which is also a good resource for auto repair.

As the above diagram shows, a serpentine belt slithers over several pulleys whose rotational energy powers different devices. The belt is typically connected to the following accessories:

Alternator
The belt helps power the alternator, which keeps your battery charged.

Power Steering Pump
The power steering pump pressurizes the hydraulic steering fluid. Without the belt running the pump, the driver could experience a sudden loss of power steering, which makes handling much tougher.

Air Conditioning Compressor
An air conditioning compressor sends fluid throughout the air conditioning system, so its functionality is key to keeping cool.

Water Pump
An engine needs the water pump to push coolant through the system and keep its temperature down. If the belt fails, it could result in your car overheating.

Water pump is driven by the timing belt that is connected to the driving shelf.

There is a video of replacing the timing belt, it shows the details belt/pulley connection.

I have found the closest video is from the second generation MDX. It is good enough for me to start from somewhere.

The lower 12 mm bolt: 22 newton-meter, 16 lb/ft
The 14 on the tensioner: 44 newton-meter, 32 lb/ft
The pulley only torque is: 59 lb/ft

Step by step protocol

 	
Prepare and line up the tools
 	
Sketch the belt diagram
 	
Loosen the tensioner and release the belt
 	
Remove the 14 mm bolt and 12 mm bolt to remove the tensioner
 	
Install the new tensioner: 16 lb/ft for the 12 mm bolt and 32 lb/ft for the 14 mm bolt
 	
Install the new belt to wrap all the component, by loosing the tensioner to finish

Unfortunately, replacing the belt and tensioner does NOT solve the problem. From Scotty’s video, he explains that it could be other pulleys. Well, we have water pump or alternator etc. He has another video that further explain how to use the right tool for the right job.

Another guy has summarized eight different kinds of noises. We will see how we can get to the bottom of it.

I have to study more and I am accumulating more videos at this point and after further examination, it starts to points to the crankshaft or harmonic balancer.

 	
This is the first video
 	
Okay, after all these "research", I think I eventually find a guy that shows exactly the the problem of harmonic balancer and how to fix it. I think this is a good video for fixing balancer wobbling.
 	
This video explains very well on what can go wrong if the harmonic balancer goes bad.
 	
Someone posted replacing the timing belt that needs to remove harmonic balancer as a start.
 	
The same guy posted the installation video as well.
 	
To clarify, the crankshaft pulley is different from the harmonic balancer.
 	
To get the job done, we would need a crank pulley tool and a puller

After all these effort, I come to this diagnosis. The wobbling noise comes from the AC clutch pulley. here are some good videos fixing the clutch.

I noticed the wobble when I wiggle the wheel bearing, so, I think it could be it. I found a very good video, and hopefully we can fix it somehow. 

This guy shows a good video tutorial.

Another guy is doing the same in vitro video.

This one is for 2003 MDX specifically.

There could be challenges removing the plat or the pulley, spacer is also critical for the AC to work.

This guy explains in more details on how to get the plat off and measure the space between the plat and the pulley.

The guys shows the important to check gap between the plate and clutch pulley.

To replace the clutch pulley seems quite simple and intuitive, but I encountered resistant from step 1. The following are the steps I need to achieve one by one

	
Remove the 10 mm bolt on the clutch plate. Luckily, done
	
Remove the clutch plate, but I can't! 


Can I use these tools to remove it?





	
Remove the clutch pulley, by removing the clip ring, then hammering it out.
	
Mount the clutch pulley back
	
Mount the clutch plate
	
Adjust the gap  between the plat and clutch pulley

Going through all these research, I want to document something related to the car AC system.

This video demonstrates how to diagnose a bad compressor.

Parts and tools for this project

Here is the serpentine belt assembly kit that I have replaced and it does not help to solve the problem.

Here is the compressor that fits 2003-2006 Acura MDX

Here is the compressor clutch and pulley that fits 2003-2006 Acura MDX

Okay, it seems that we may have to be prepared to replace the compressor!

Main steps are here as shown in the video:

	
Remove the serpentine belt
	
Remove the coolant fans to get room
	
Discharge all the freon
	
Disconnect the high/low pressor connection
	
Remove top two bolts from the top, two bolts from the bottom
	
Unplug the connection socket
	
Remove the metal bar to get more room
	
Remove the old ac compressor
	
Reverse the above steps and make sure all the connection are secured, reinstall the belt
	
Be sure to use the new o-rings for pipe connections.
	
Re-charge the freon
To work with the pressor, here is a good video on this.

Work on the tie rod

Very good TRQ video

2007 Honda Odyssey

Another friend has a car AC issue, his car is Honda Odyssey 2007 and we diagnose that the problem could be the “coil” failure

He found a video, but I feel that the person did not record those difficult steps.
So, I searched around and found another video, he did not record the whole process, but at least he mentioned a few challenge steps:

He mentioned that the location of the compressor makes it hard to reach
The first trick is his wife helped to remove the serpentine belt from the top.
He mentioned the tool to hold the cap when he tried to loosen the 10 mm center bolt.
He show two different ring snap plier, they are very hard to be removed.
He mentioned to using a rubber mallet to snap the pulley off

These are difficult steps he encountered, we can see more but hopefully less.