after changing my timing belt and water pump on my 95 ls my car idles normal at around 500-800 rpms... but its making a weird noise like it cant stay on.. but the needle is steady at idle and the car still runs strong.. i had a mechanic look at it and he said its leanin out.. like its fine when its cold and the idle is a little above 1000 but then when its warm it starts makin that noise comin out the exhaust and the mechanic says it runin lean at idle... can this damage my engine?? or is there a way to get it to stop leanin out???

 

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