brake caliper piston won't push out
 

I replaced a new brake caliper on 2002 Mitsubishi lancer es and I also bleed the brake hose/line...I think I got most of the air out on the new caliper when I bled it. but when I press on the brake pedal and go for a test drive, the piston doesn't seem to press against the pads or rotor...I know because I touch the rotor with my finger after the test drive and its cold...not hot like the other side that's working properly...any idea how to fix this?

I dont think touching the rotor is considered a proper diagnostic procedure.

well I took the wheel off and look at the piston itself....there's a large gap between the piston and rotor....I also had someone press the brake pedal while I observe.....no movement on the piston whatsoever....

check your brake line, piston could be seized though

Is the caliper new? Or rebuilt? Could be a number of things. I've seen everything from a collapsed brake hose to a newly rebuilt caliper defective right out of the box.

the caliper is brand new....not sure if brake hose is collapsed but when I bleed the line from the bleed valve, brake fluid flows out about half a liter of brake fluid

Just to make sure we're on the same page. Where did you get the caliper from? Brand on the box? Etc. Any other issues with the brakes besides that one side?

If you are able to bleed it, fluid is there. Sounds like a defective caliper, assuming it's being bled properly. It's possible.

i got it online.... Drivestar is the brand name....i only replace the right side not the left

Just to make sure this sounds legit....when u press on the brake pedal...the piston should push outward from the caliper housing....correct? Unless theres leakage or the hose is collapsed or broken....but if the caliper is able to bleed....to me the line flows freely no obstruction there.

Yes it should, but if the caliper is bad the piston will just be there "frozen"