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Engine makes tapping sound

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Old Jul 30, 2006 | 04:28 AM
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Default Engine makes tapping sound

Looking for opinions on what this might be. My engine started making a loud tapping noise that i think was coming from the head, i let the car sit for two days thinking i had a major problem then i go start it tonight and the tapping is still there gets faster with higher rpm's the i stomp on the cas hit alittle boost and the bov goes off and the sound goes away whatever was stuck or not right is moving in line with the rest of the engine. now i know im gonna have to do something about this and im thinking its definatly valetrain related any idea's??
Old Jul 30, 2006 | 04:55 AM
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you could be knocking. have a shop check that out asap
Old Jul 30, 2006 | 04:57 AM
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did you rebuild this engine? maybe the wastegate is still messed up..
Old Jul 30, 2006 | 05:05 AM
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you got enough oil in the car
Old Jul 30, 2006 | 06:21 AM
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watching
Old Jul 30, 2006 | 07:04 PM
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Does it knock at engine (crank) speed? If so it is on the crank (rods, mains). If it knocks at half engine speed it is on a cam.

Also, is it a well defined knock, or more of a random rattling? The latter would sound more like valves.

Finally, to check for a knock on the crank. Run the engine up to about 2500 - 3000 rpm and then feather the throttle back and forth. Preferably under load while driving. If it rattles louder as you feather off that is one sign of a possible rod knock.

Just a few more things to try and consider.
Old Jul 30, 2006 | 07:30 PM
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spunt rod bearing? Has happened to a few 05's
Old Jul 31, 2006 | 12:12 AM
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Yeah... could be valves. Ive had that before... no fun.
Old Jul 31, 2006 | 12:18 AM
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Default engine makes tapping noise

Rod knock buddy boy! get it checked out soon!
Old Jul 31, 2006 | 01:03 AM
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Dont panic him.. more often than not people take thier car in with a "knock" and it is not one.

Just check the things mentioned and see what you can rule out. And it isnt a spun bearing or the whole thing would be done by now. When a bearing spins you will know pretty quick. It sounds like you have driven a few times since it started.
Old Jul 31, 2006 | 01:21 AM
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reminds me of stu_gotti.....that really sucked
Old Jul 31, 2006 | 06:38 PM
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yeah take it from me... definitely not a bearing... heh heh you don't get much warning when one of those decides to go as far as rod knock.. im almost sure that would imply one of your bearing having issues and i go back to my previous point that our bearing don't take much time to go into total loss and self digest... If it was a rod, you'd know it my number four rod was knocking after my bearing went and you wouldn't mistake it for anything else in the world lol especially if its more of a "tap" noise as you say it is... I wouldn't sweat it too much... however i would get it to a dealership ASAP... my friends mirage has this mystery tap and we've adjusted his valves a hundred times by now i swear and its still there, turns out some mirages just tap according to like three different dealerships... could be someting very minor...
Old Aug 1, 2006 | 09:05 AM
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Dont worry nothing can panic me at this point its just a motor can always get a 3rd
Well the started the car yesterday and let it warm up, reved the car into boost without load and tapping sound is gone. let it sit overnight started it today took it home flushed some oil and filled her back up with mobil 1 took it for a drive and put about 50 miles on it and tapping hasent come back. My though is this when i drained the oil it was pretty dark and nasty im geuessing alot of deposits as the motor was problley sitting in a wrecking yard for awhile. even though it was fresh oil after around 150 miles of driving its got kinda nasty and maybe there was some sludge in the head and something was sticking well no tap now i will keep you guys updated also i have a spare head from old motor so i can always go that route if need be. thanks for all the imput guys.
Old Aug 1, 2006 | 12:57 PM
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Originally Posted by cdp1279
Dont worry nothing can panic me at this point its just a motor can always get a 3rd
Well the started the car yesterday and let it warm up, reved the car into boost without load and tapping sound is gone. let it sit overnight started it today took it home flushed some oil and filled her back up with mobil 1 took it for a drive and put about 50 miles on it and tapping hasent come back. My though is this when i drained the oil it was pretty dark and nasty im geuessing alot of deposits as the motor was problley sitting in a wrecking yard for awhile. even though it was fresh oil after around 150 miles of driving its got kinda nasty and maybe there was some sludge in the head and something was sticking well no tap now i will keep you guys updated also i have a spare head from old motor so i can always go that route if need be. thanks for all the imput guys.
A) GO to Firestone and have them vacuum your oil out. They have a machine that can pull some of the sludge out.
B) Run one of those oil/detergents for about 500 miles without hitting any boost and then change your oil again.

Either of these should clean out your heads.
Old Aug 1, 2006 | 06:46 PM
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You can also dump about a quart of oil out and replace with good automatic transmission fluid. Then change the oil in a few hundred miles. For smaller amounts of deposits this works pretty well. I seriously doubt you have a large amount of sludge in your engine at this point. Ford 4 banges were notorious for getting trash in the valvetrain and rattling. I have fixed a few of these using this method. Auto tranny fluid is very high in detergent content. Just drive it easy and only do it for a few hundred to 500 miles before changing it. Stay out of boost and dont beat on it while doing it.
Old Aug 1, 2006 | 08:19 PM
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I had a tap that sounded like my head and then I started pushing on different parts to track it down - found out I had a downpipe to spipe bolt just a little bit loose but it sounded as if it was coming from the motor.

Only makes the sound after I had run it for a bit.
Old Aug 1, 2006 | 08:25 PM
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Yeah.. you would be suprised how many "knocks" turn out to be something completely different. Definitely rule out any other more obvious or simple items before doing anything else. You can also place a peice of hose tot your ear (or just go out and get a mechanics stethiscope) and poke around on the engine while it is making the noise until you pinpoint it better.
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