I have a 2008 mazda 6 and I had a cold air intake put on it about a year ago but here recently it has been raining harder and more in my area and when I went over 45 mph in the rain it felt like I was getting a hydro lock or the car was kicking back 5 minutes later my check engine light comes on so I get it tested and the code came up for a fuel line problem but the check engine light goes away when everything dries up in the area and my car is back to normal so I'm doing research now and find out I need a bypass valve so water won't get into my intake? I have a cheap L4 CAI and I really don't know how to install this bypass valve because it requires cutting the piping of the CAI really confused I need help finding out where I should cut the pipe and what I should do

 

I am not sure about your engine layout/configuration.
However, I will tell you something that will help you, as this is my speciality and I have done this process.
F___ the bypass valve. Really don't know how this will stop water hitting your MAF sensor (Mass Air Flow Sensor located in intake tube). It may help somewhat preventing water getting in to engine, but your wet MAF will still be causing your issues. This by-pass valve only solves 1/2 the problem.
Unfortunately most cold air intakes are long and the filter is located in front of the driver's side wheel. If this is your configuration, I can help you.
If your filter is already up top with a heat shield (like K&N's is for the 4 cyl 2.3L) then you only need to do the water shield deflector.
My Mazda 6 is a 2006 V6 so i'm hoping they are similar.
I have a Short Ram Air Intake that is a Cold Air Intake! It gets at cold air and is shorter than the normal Cold Air Intake. My Air Intake has a special HEAT SHIELD that isolates the colder air from the hotter engine compartment air. The filter is mounted higher, away from the water.
If you look in front of your driver's side tire you will see slotted openings in front of it. In front of this is normally where the cold air intake filter is located. When you drive in the rain and through puddles, water gets splashed forward on to your air filter. I know, I originally had this issue. Then I got smart and switched to my current set-up.
You need to do 2 things: 1) install a water deflector spalsh guard 2) install a heat shield
The water deflector keeps water lower yet lets air go by. See pics.
The heat shield is mounted to the car frame with cut-out for intake tube, lined with weatherstripping or carpet or special insulation that doesn't come apart easy especially after you paint it black!(do not buy pink insulation with many bad fibers). This heat shield must be high enough to seal to the hood. You also must put something above the fuse box to seal it to the hood. I also have a removable piece above the intake tube as well.
I had to add the water shield aluminum piece 8" wide x 7" tall, 1/8" thick is fine, (bolted with 2 1/4" elevator bolts---bolts with large flat head---through lower plastic fender) becuase water would still spray up without it. Last pic shows this best. All of my water intake problems are solved. I also leave this set-up for the winter time without snow clogging issues! I do remove the removable piece above the intake tube to let some warm air over there in winter time.
I also removed the oem intake resonator located under the air box.
I also would suggest clean your MAF. Dirty water on there is not good!
There is plenty of air that comes in thru front grille.
Hope this helps in getting your brain working for a proper permanent year round fix!
Spnt a lot of time on this post, good thing pics were done already.

 

I don't think that it could be sucking in enough water when it's raining. Usually the only time I've even seen an engine hydro-lock is when the intake becomes fully submerged