gta 4 XBOX 360 i done the health cheat and saved it if i restart the game will i be able to get the achievement or is it gone fo ever ?
In order to unlock the achievements you would have to completely start the game over again. The reason the achievements became locked was because you used the cheat code. Rockstar in order to make unlocking the achievements a challenge made it so the game locks the achievements that corresponds with certain cheat codes.
So in order to be able to unlock the achievements you are trying to unlock you need to restart the game from the beginning and play it through without the cheat codes

If you've saved, it's gone forever.
References :
In order to unlock the achievements you would have to completely start the game over again. The reason the achievements became locked was because you used the cheat code. Rockstar in order to make unlocking the achievements a challenge made it so the game locks the achievements that corresponds with certain cheat codes.
So in order to be able to unlock the achievements you are trying to unlock you need to restart the game from the beginning and play it through without the cheat codes
References :
If you saved it then the achievment has gone forever and you won;t be able to get it again – sorry.
Hope this helps!
=]
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I've got the game.
Well i went through the game using the odd health cheat here and there and i had no problem getting any achievements once i'd finished the story. I think as long as you don't use the cheat WHILE you're trying to get the achievement you should be fine.
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My Own Game Experience