The Chargers were manhandled in Sunday's 17-10 loss to the Cincinnati Bengals, the first NFL game to be blacked out this season, to drop to 5-7.
It was their fourth loss in five games.
"At critical times we have made too many mistakes," said McCoy, who was never a head coach at any level before getting the job in January after Norv Turner was fired. "Go back to every game, you look at certain situations where we haven't executed. We just haven't gotten it done. It's about being more consistent week in and week out and not just at certain times but the whole game."
The loss came a week after a thrilling 41-38 win at Kansas City.
The Chargers made a big deal about having four of their final five games at home. After Sunday's loss, the Chargers are 2-3 at home this season after going 3-5 at Qualcomm Stadium last season.
None of the remaining three home games have sold out.
"We've got to go out and win games," McCoy said. "We have to do a better job. The players, coaches and the organization have to do their job better."
The Bengals exposed the Chargers' defense by rushing for 164 yards and getting an easy 21-yard touchdown pass from Andy Dalton to a wide-open A.J. Green.
"You know what kind of football team they are, the division they play," McCoy said of the Bengals, who lead the AFC North by two games. "We have to do a better job of being gap-sound, where you are supposed to be on the run fits, certain things. Not running through the back side. A number of little things. The disappointing thing is there were certainly times we weren't solid enough at the point of attack. We had it stopped, but the guy gets five yards somehow. For some reason or another, we had four or five plays there where they should be zero runs and they have five, nine yards whatever they are. We've got to stop that."
The Chargers blew a zone coverage on Green's touchdown.
"It all starts with knowing what to do," McCoy said. "Physically you are going to get beat by somebody. There are some great players in the game. No. 18 is a very good receiver. You are going to get one-on-one sometime. But you can't give him a free touchdown where he is not even touched walking down the middle of the field in the red area. That's one of those things you've got to know what to do first. You can't have a breakdown somewhere. All 11 have to be on the same page on what we had to do and they were not. You just gave them seven points."
On Sunday, McCoy will match wits with two-time Super Bowl-winning coach Tom Coughlin and the New York Giants, who have climbed to 5-7 after starting 0-6.
The Giants' offensive coordinator is one-time Chargers coach Kevin Gilbride, who like McCoy was hired based on his credentials as an offensive coordinator. Gilbride went 6-16 before being fired six games into the 1998 season.
And then there's Eli Manning, who made it known shortly before the 2004 draft that he didn't want to play in San Diego. The Chargers drafted Manning anyway, then traded him to the New York Giants for Philip Rivers and two other picks who turned out to be linebacker Shawne Merriman and kicker Nate Kaeding.
Manning has won two Super Bowl rings with the Giants.
Talk all about Sunday's Chargers-Bengals game inside the message boards.
Bolts in free-fall after loss to Bengals
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