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Discussion Starter · #1 ·
Ive noticed some knocking not sure if its a lifter or what it is. it not real loud but i notice it. when engine warms up i hear it even less but can still hear it. also car seems to idle a little high but does kick down after a min or so. but it will rev high agaim something sticking maybe.
 

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Mileage?

It could be the tumble flaps. That is normal, and can happen at any engine age. First you need to determine where the sound is coming from. I had a friend who thought that his engine was knocking, but it turned out to be a loose bracket that was rattling.

Use a long screwdriver or a long dowel, stick, or something of the sort to listen to the engine while it runs. You simply hold the "probe" on the engine, cup the other side to your ear, and listen. You are searching for where the sound is loudest. Don't get too close to the accessory belt- obviously, since the engine is running. This will enable you to determine where the sound originates from. For example, tumble flaps sound like bad valves until you start listening to the engine. When listening to the valve cover, you'll hear the whirring and movement of the valve train, but none of the tapping. Then when you listen to the intake manifold- the tapping is there, verifying that the sound is not bad valves, but the tumble flaps.

Engine knock due to bad rod bearings will get worse under certain conditions. It will be worse, or louder when the engine is under a load like climbing a hill. It will be worse as the engine warms up.

A knocking accessory, like my friend had with his loose bracket, is a big more difficult to find, but it is simple to cross off more serious engine related causes. Engine related knocks like a rod knock will knock in time with the engine. If you have an intermittent knock, then it's not an internal engine related knock. Those are on time all the time. Loose brackets can seem to be in time with the engine because the vibrations of the engine are what are causing the knock, but you will hear some off time knocks nearly all of the time. Those knocks will also be much sharper and tinny in most situations whereas internal knocks are more muffled.
 

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Discussion Starter · #3 ·
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Thanks for getting back to me. i did was you suggested. i didnt hear much noise coming fron the engine itself. the knocking seems to come from the area of the black plastic housing i guess from where the tumble flaps are you mentiond. what can i do to resolve this issue just that noise makes me on edge. the car runs alittle rough can that be from bad fuel injectors and can they make that tapping sound
 
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