hey, i got a question. i have a 92 rs with a 305 tbi. last night i noticed this ugly sound. its like a rattling or kinda like a tapping sound coming from the engine. it gets louder when i accelerate and lower when i deaccelerate. is this a blown piston or what else could it be? if it is the piston...would it be cheaper to fix it or replace the engine? please respond quickly. thanks in advance.

 

header came loose and made same sound...as exhaust seeped out around the gasket.

hard to tell unless you start digging into it. loose rocker arm maybe? valve lash

could be lots of things

 

Could be a ton of things, like loose rocker arm, bent pushrod, spun bearing, or it may not even be in the engine, like loose torque converter bolts (assuming you have an auto tranny).

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Does it make the knock when the car is idling? If it doesn't then it could be(and I know this will sound strange)low octane gas. Are you using reg., mid., or high octane. Now if it does it while the car is idling then you could have a lot of different problems. Just a thought.

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yea it does it when idling. it just gets worse and worse when u accelerate. i wanted to put a zz4 in but guess this kinda changes things cuz i dont have the money for it yet. anyone know of any cheap performance engines?

 

cheap and performance should never go in the same sentence . dont go the "cheap way" you are much better off to save money and do it once and do it right......TRUST ME!!

as everyone else said,could be many things from the noise,could be a few minor things, or you could need a new engine, but let us know when you find out. good luck!!

http://people.ne.mediaone.net/gdm

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this is off the wall, but have you checked your oil? It could be valve tap caused by low oil.

Clayton