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Tapping noise


adallak

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Here is a good date night for you! Drive to the darkest part of town, with no lights and park the car, leave the car running. Look at her lovingly, and tell her there is something you want her to help you with! Go around the car and open the door for her and take her hand and help her out. Slowly lift the hood telling her how important this is for you. Tell her to bend over carefully,

:lol::lol::lol: Mike, you are such an incurable romantic! After I say her there is something I want her to help me with :rolleyes: ..I will not be able to get out the car! Been there done that. :D Finding te darkest part of the town with no lights is another challenge :lol:

Here is what I am going to do - I will tell her if it is really the #1 bearing I'll marry her. If it's not she has to wait for another 100,000 miles.

epricedright, of course letting her to powerbrake is safer for her but... do you remember the story with a Mercedes? :o

The saddest thing in life is wasted talent

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  • 2 weeks later...

could the tapping noise be caused by detonation? It is noticeable only when the temperature is 190 and up under acceleration or powerbraking. If the problem say,

EGR valve would it be temperature depending?

The saddest thing in life is wasted talent

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A cracked exhaust manifold will open up and leak at different temperatures and you will notice it more when the engine is under load (like the power braking maneuver). A cracked manifold or leak at the take down pipe will sound very metallic and tap-tap-tap just like a tapping lifter sounds.

thanks for the reply bbobynski. Does it make sense to lift it up and powerbrake to "see" the source of the noise? I assume it is harmless if it is really exhaust related, right?

The saddest thing in life is wasted talent

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this is one of those times where it would be applicable to record the noise so we can hear it :) hehe.. another question is if you can 'feel' the noise. you can't really 'feel' an exhaust leak but if you can feel your accelerator pedal or some part of the car knocking with the noise then it's somethign else..... can always use the big stick against motor and ear trick :)

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great idea bigfoo! I actually can powerbrake from outside. Only thing I need to do put a stick between the driver seat and brake pedal and move the seat forward. Then put it in drive and increase RPM by hand listening watching the motor with open hood. I am going to try it tomorrow.

The saddest thing in life is wasted talent

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heh.. to power brake i push the emergency brake all the way down, stick the car in reverse and then move the throttle from inside the engine. I wouldn't trust a stick against the brake and i especially wouldn't put it in drive, always in reverse in case something does let go it doesn't run you over, then just take a stick or a hose and try and listen/feel for the noise, you can also hear exhaust leaks when you rev the engine up real high and let off the throttle instantly it will 'puff' some , especially when it's in gear like you are going 40 in 1st gear at 5000 rpm then let off the gas but leave it in 1st should hear some puffs

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Thanks everybody for the suggestions.

Bigfoo, my car insurance does not cover funeral expenses so I hope a tree will stop the car before it runs over :huh: I do not trust the emergency brake too much. Having it in Reverse is a healthy idea though.

Kqer2, thanks for the offer to host the sound clip. The best description of the noise is Maxim machine gun. I believe you heard one on History channel (the most entertaining channel after FoxNews :D ). If you did not hear Maxim, keep watching the History channel - there is always some shooting up there since " The mankind history is the history of wars".

Scotty, do the exhaust gases change their ways depending on gear selection? Why not in Neutral?

The saddest thing in life is wasted talent

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When you put your car in drive you shift your engine a bit, that puts torque on your exhaust system and it could be pulling the crack or exhaust manifold away from the head if its loose. Also, it only happens when your engine is hot, when the metal expands slightly. I am betting on a crack or bad exhaust manifold gasket.

About 3 years ago I helped a guy in Amsterdam get a 4.9 engine shipped to him from my junk yard, his engine was trashed, not only did his engine have a cracked exhaust manifold but the one I sent him was cracked. When I checked with the junk yards they told me it was common for them to get exhaust manifold requests due to cracks.

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When I checked with the junk yards they told me it was common for them to get exhaust manifold requests due to cracks

thanks Mike, it makes sense. I think I can live with a cracked manifold right?

The saddest thing in life is wasted talent

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When I checked with the junk yards they told me it was common for them to get exhaust manifold requests due to cracks

thanks Mike, it makes sense. I think I can live with a cracked manifold right?

Unless you can smell exhaust fumes, the guy in Amsterdam couldn't stand the fumes. One of these days maybe you can get a good look at it

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