Engine is making tapping noise at rear lower end

What's That Ticking Sound Coming From Your Car's Engine?

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Apr 18, 2014 - My engine has developed a strange ticking sound. Its whisper-quiet before an oil change, and then makes a loud tapping after a new filter and ...

Engine Tapping - Auto Repair Help

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ENGINE MAKES TAPPING NOISE WHEN STARTED by Mark Davidson. SYMPTOM SUMMARY The engine emits a tapping noise on start up. The noise may ...

Engine Ticking Clunking Noise - Repair - YouTube

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One of my vehicles started making a rather disturbing sound so I went to investigate and to hopefully fix it.

Would likely require a complete tear down and rebuild of the engine. A loose piston rod will cause a loud knocking noise. You said very very loud, so I think that would be the engine lower end, a rod or crankshaft or piston problem.
If that's the case, you'd be better off just replacing the engine.

Are you absolutely certain the noise is lifter tap and not an exhaust leak? These are pretty well known for breaking exhaust manifold studs, or even cracking exhaust manifolds. The noise will be present on a cold engine but might go away as the engine heats up and the manifold expands. Maybe that's why it seems to go away after adding additives or changing the oil. It gets just enough heat in the engine to fool you in to thinking the issue was resolved by adding the oil/additive. Are you always adding to a cold engine?

-Rod

Ticking sound could be coming from a Coil-on-Plug, or a pcv valve, or (hope it's not) a valve lifter which could be sticking. Sticking lifter noise often disappears when rpm's change, or the noise comes & goes. try changing the motor oil & filter right after adding an Engine-Flush Treatment to the motor oil, running the engine for 10 minutes at idle with treatment added to the oil, then draining the oil & changing filter while oil is still very hot. That last part is very important, so be careful not to burn your hands - be careful. -- The sticking lifter is a likely cause if motor oil has not been changed at frequent intervals in the past (every 3-4K miles) -- dirty oil causes sticking lifters.

Maybe.
Carbon buildup is a common problem with today's engines and the fuel we use.
The computer would have ******** the spark timing when the tapping was going on which would have caused the power loss on acceleration.
Its possible you have damaged the bearings and valves from running on low oil, especially by the previous owner. The engine can run on one quart of oil as long as it makes enough pressure to keep the warning light off, but still not have enough volume to reach the valves on top of the engine.

Hi depending on the amount of miles that are on your vehicle, it may be the engine has loose clearances, and the oil may take time to pressurize enough, and the engine to warm up enough, for the noise to go away. If it is a deep thud noise, it could be lower end wear. If it is a light tapping, it could bein the upper end. These are examples of worse case scenarios. On a lighter note, oil level is crucial, and some aftermarket oil filters do not have a bleedback valve in them, causing oil to drain comletely back into the pan, when the engine sits. A known good filter, such as a factory ac, will have this valve. I would suggest an oil change, with an anti bleedback filter, to see if this improves. If not, possible excessive clearances may cause this. Additives may actually cause other issues. If the noise does not lessen with an oil change, I would get an opinion from a reputable garage. Good luck...Coop

might be the valves have been damaged running without oil
- or the crankshaft / camshaft / main bearings
most probably you have to let the engine be rebuilt by a mechanic
(expect cost of more than US$ 2.000)
or get another (used) engine at a scrapyard

If it is a 'squealing' noise it's probably the alternator/power steering drive belt. Before you turn on the engine in the morning, lightlt smear or spray some oil on the inside of the drive belt to lubricate it. If the squealing stops/disappears, then that's the fault ..

That squealing noise can be caused by an incorrectly tensioned belt, or a worn belt. Replacement is the only option.

The other frightening sounds can best be described as 'rattles' or 'tapping'. When a car stands overnight all the oil drains back into the sump (oil/pan).

There are two things (usually) that can be cause the rattle/tap:
1. Because the oil hasn't been pumped around the system, at start up worn big end bearings can rattle and tap on the crankshaft until the oil 'fills the gaps'. The tapping/rattling goes away as the engine warms and oil is pumped around the lubricating system.

A 'bottom end tapping' is a symptom of worn big ends (they are bearings at the bottom of the piston and fit around the crankshaft).

2. A rattle/tapping from the top of the engine can either be a worn camshaft or 'lazy tappets'. Again, when the engine warms and oil gets to the camshaft and tappets (also called 'hydraulic lifters) the noise will disappear.

If your car has this rattling/tapping noise - identify whether it is coming from just under the rocker box (ie the camshaft/tappets..) or the bottom end of the engine (big end bearings).

If the noise is coming from the top of the engine, try an oil change with a can of thick 'additive' included. A lazy tappet (lifter) isn't too much to worry about. A worn camshaft will affect the performance of the engine, though continue to do its job. An oil change with an additive included may help in quitening things down.

A bottom end tap/rattle (or 'knock') - the sooner that is sorted out the better.

Just add oil, or better yet get an oil change, your oil is obviously low, antifreeze is not a fix all.

Could you Explain this in Detail????