All new plumbing and faucet- low pressure- sprayer not working

We just bought a twenty year old mobile home and replaced all the plumbing and installed a new Moen 4 piece kitchen faucet. Our water pressure is very low with the hot and cold lines and the sprayer doesn't work at all. All the other faucets are work fine and the water pressure is great. I looked for the answer on the moen site but I didn't find a answer there. Any ideas that can help?
By the way, no leaks or blockages and everything is brand new from pipes to faucet

 

Welcome
Try removing the aerator and flushing out the lines and faucet first.
You might need to replace the valves under the sink. Opening and closing an old valve could cause debris to enter the supply hoses and block flow. Basically the washer inside the old valve disintegrates and the valve needs replaced.

 

You need to temporarily disconnect the faucet from the supply pipes. Try turning on the supply pipe into a bucket and see what the flow is like. If it's pouring in like it should be, it's likely an aerator or filter in the faucet got clogged with some of the new pipe gunk.

Many newer faucets have a filter or aerator in the handle or spout to make it eco-friendly and low-flow, but easily clog with any little debris in the line. Look at the parts diagram in the Moen instruction manual to find the aerator/flow control filter. If you share the Moen model number, we can help.

Of course, if your initial test results in only a little water dribbling out of the supply pipes, your issue is elsewhere.