The following are known Action Replay Codes for Konami Krazy Racers on Nintendo Game Boy Advance (GBA).
These codes were also known as GameShark Codes and in most cases will work on both devices.

These codes are for the U.S. version of the game.

Master Code – Must Be On
91225994
a91c34f1
d6f94e26
d126a0fe

No Laps To Finish
0956056e
9980cd5e

1st Position
c979bd33
7e7c1e17

999 Coins
137482ee
1a58f971

Inf Retries
6f7724c4
26a1c947

Weapons Max Power
db4b7040
ccab7ca0

Have Turbo
c3101c6d
53a7e924

Have Eyewrap
2d662d25
9a793e7d

Have Timebomb
9aa55f3e
fe1ad0d2

Have Scooper Drill
8b3397f6
d1fc476f

Have Barrier
2106993c
ebbdb8ca

Have Blue Missile
eb99390c
3b9b2270

Have Red Missile
5ee6fd06
8b41e393

Have Ice Crash
cec757c4
a1edf4ac

Have Electric Batt.
d394ef8c
9cf717f4

Have Pig
66d0b3e4
aa5c45d1

Have Hover Mode
559ff7d4
92dbbc36

Have Ally Spark
e4ffe091
cbd1c6a8

Press AR Button: Slow
dbba3a89
4cb74b94