My car would not idle. Changed fuel pump. Still have problem. on 2011 Kia Soul

You have to keep revved up so will not die. Have changed the fuel pump. Now they say that cylinder 1 is not holding compression. Please explain what this means.

Asked by for the 2011 Kia Soul
1 answer 1 comment
if its not holding compression then you either have a bent valve or a broken ring but I would check with the dealer to see if it is still under powertrain warranty.has it got a lot of miles on it? I would also check for a vacuum leak
It only has 69,000 miles and has 100,000 warranty. Everything you mentioned should be covered under warranty right?