When switched to filtered water on my kitchen faucet water comes out of both sides like the switch isn't working brand new filter on 1year old unit?

SOURCE: Loss of pressure in kitchen faucet - Price Pfister

Your problem is a simple one.

1. Turn off water to faucet.
2. Place a towel(s) in the base of the sink(s) to prevent any parts from going down drain.
   
3. Remove the handle to the faucet. (single handle only)
   
4. If not a single handle then remove spout from faucet.
5. If a single handle remove cap carefully and any loose parts.
6. Gently turn spout side to side while lifting to remove.
7. You will see a hole with a very small valve where the water comes out to the spout on the base of the faucet.

1. Remove this valve (which is a backflow preventer) and replace.
2. Reassemble and test.
   

Problem solved.

SOURCE: low pressure and flow on hot water side of single handle faucet

It could be one of two problems, one simple, one serious.

• Easy fix
  

1. Turn off hot water angle stop under sink to faucet.
2. Remove supply line from hot angle stop.
3. Place end of supply line in a small bucket to catch some water.
4. Turn on cold water for a couple of seconds and backflush debris from faucet.
5. Reconnect supply line.
6. Turn on angle stop and test
   

• Complex fix

If you have steel pipes you may be experiencing reduced flow due to corrosion in your pipes. Reduced hot water pressure in the kitchen faucet is usually the first sign since this is the faucet that is most used in the home.

Repiping is a job for a professional. Another symptom you may need a repipe is orange colored or rusty water.

SOURCE: Kitchen Faucet 6310 020 White - HOT WATER SIDE NOT WORKING

The faucet cartridge is more then likely blocked and the faucet will have to be disassembled in order to unblock it.
While it is disassembled you should slowly turn on the water lines to make sure the water ways in the faucet are clear. And thoroughly check the cartridge for damage. Replace if necessary.
Replacement Cartridges can be purchased at most plumbing supply houses or Big Box Stores such as Lowes or the like.

SOURCE: water is plugged by minerals etc in my Hansgrohe kitchen faucet

You will need a flat head or a knife. You sould be able to pry it apart if not they are so cheap, pick one up at walmart, lowes etc. Bring the old one with you. Some of the tread patterns are diffrent

SOURCE: kitchen faucet single handle pull-out. The base of

I have the same problem with an American Standard Reliant Kitchen Faucet that wont swivel anymore. I called American Standard and they are sending me the replacement parts to fix it free of charge, I have had mine 6-7 years and they said it was under warranty. Call 800-442-1902. Good Luck