What are dead works?

…unless we have been washed in the blood of Christ, all our good deeds are worthless, useless, vain, and dead. Live right. Eat right. Give right. Die right. The truth, however, is that only faith in Christ saves - not our works. There are two kinds of dead works:

1.Those works we do before we are saved as a means to try to please God (e.g.filthy rags as in Isaiah 64:6)
2.Those works we do after we are saved that are not pleasing to God (e.g. wood, hay, and stubble as in 1 Corinthians 3:11-12).

In other words "repentance from dead works" is the teaching that we must repent from trusting in our own dead works to save us. Instead, we must trust in Jesus Christ alone for salvation.

 Galatians 2:16

yet we know that no one is justified by the works of the law but by the faithfulness of Jesus Christ. And we have come to believe in Christ Jesus, so that we may be justified by the faithfulness of Christ and not by the works of the law, because by the works of the law no one will be justified. 

Ephesians 2:8-9

 For it is by grace you have been saved, through faith—and this is not from yourselves, it is the gift of God—  not by works, so that no one can boast.

2 Timothy 1:9

He is the one who saved us and called us with a holy calling, not based on our works but on His own purpose and grace, granted to us in Christ Jesus before time began, 

Titus 3:5

He saved us not by works of righteousness that we have done but on the basis of His mercy, through the washing of the new birth and the renewing of the Holy Spirit, 

Romans 3:21-22

But now apart from the law the righteousness of God (although it is attested by the law and the prophets) has been disclosed – namely, the righteousness of God through the faithfulness of Jesus Christ for all who believe. For there is no distinction, for all have sinned and fall short of the glory of God.