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Discussion Starter #1
Hi I am new to this but not sure what else to try. I bought a used 05 altima in 2014, since I have replaced an alternator, A/Traxle seal(front pump), crankshaft seal, engine mounts, the cat was punched out at garage that worked on it, the transmission sensor was resoldered due to bad shifting. After all of that while driving and I old come to a stop the engine would die and the oil light would come on even though I had enough oil. SO I replaced the oil sending unit that didn't fix it, so then I checked the filter inside the oil pan, and in the pan I found small pieces of teeth like metal to which we have cam to conclusion may be balance shaft gear teeth, the car runs ok, does not leak anything, does produce white smoke at startup, does use a little bit of oil, number one spark plug has oil in it, does not leak or lose antifreeze, gas usage has not been as good as when I first bought, I had a compression test done from a local guy it as 90 90 90 70, but after reading I think he may have done it wrong and I can't find what the correct pressure should be on my car. I have been learning slowly so bear with me if my mechanical lingo is somewhat off. ANY way the car does have an engine noise I only notice during acceleration but isn't present when gas isn't being pressed. QUESTION is does this sound like balance shafts and gear being bad, can I cut the chain in the oil pan for now? what is a normal compression test result? the car has 174,000 I drive it, and it seems to run ok with xception of the noise I mentioned. Any input or thoughts would be appreciated. thank you all
 

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The small pieces of metal you found in the oil pan could from the balance shaft assembly or it could be from the cam gears, the crankshaft gears or the timing chain guide. You would have to remove the timing chain cover and do an inspection. If I was you I wouldn't fool around with trying to cut the balance shaft chain out. If the assembly is damaged, the proper thing to do is replace the assembly.

Does the oil light come on when the engine is idling; It sounds like you may have low oil pressure which could be caused by several factors. Worn rod/main bearings. Plugged up oil filter. Dirty oil pickup. Most of the time it's the oil pump which may be worn and not producing the proper oil pressure/volume. You can check the pressure very easily by installing a temporary mechanical oil pressure gauge. You would remove the oil sensor which is located next to the oil filter and install the mechanical oil pressure gauge in it's place; you may need to get an 1/8 BSPT to 1/8 NPT adapter to hook up the gauge. Very low oil pressure could be causing the cam chain tensioner to not properly operate which could cause the noise you're encountering.

With the engine fully warmed up, the pressure should be as follows:
idle - at least 14 psi
2000 RPM - 43 psi

The proper way to do a compression test:

Warm up the engine to full operating temperature.
Release the fuel pressure.
Remove the ignition coil and spark plug from each cylinder.
Disconnect the fuel injector harness connector on each injector to avoid any residual fuel injection during the measurement.
Install the compression tester with the adapter into the spark plug hole.
With the accelerator pedal fully depressed, turn the ignition switch to the “START” position to crank over the engine.
When the gauge pointer stabilizes, read the compression pressure:
Standard - 181 psi
Minimum - 153 psi
 

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Discussion Starter #3
Thanks for your time in replying and detail was great, I guess I forgot to mention, the oil light problem was fixed when we dropped the oil pan and found the pieces of metal, it had the oil pan filter clogged, now it runs and I no longer get the oil light or stalling, it runs ok now with the exception of the rattling. If I'm driving about 65 I can hear a tapping if I accelerate it goes away and if I let off the gas it goes away. Just has me stumped, and thank you for the compression test specs. Gonna do that when I can get someone to do it. Strapped for cash but little by little I guess.
 

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Sup Mod keeping the peace
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The rattling sound could be caused by a problem with the timing chain or balancer assemblies. IMO, remove the timing chain front cover and find out where those broken pieces came from. With all those broken pieces, you could have a disaster waiting to happen. The rattling sound could also be caused by excessive piston-to-wall clearance.
 

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Thanks guys, I just yooknoilmpan off the other day to check out cutting the balance shaft chain, we found a small amount of copper colored shavings in there and from what I've read, it seems I may be in nerdy of a new motor soon, so I haven't drove it since, I can't afford a new/used motor so I guess I will throw my hands up in defeat :-(
 

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Ha ha sorry guys, look past my goofy spelling my phone has some letters that don't work! And if I do not pay perfect attention it just makes up it's own words!
 

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Sup Mod keeping the peace
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Thanks guys, I just yooknoilmpan off the other day to check out cutting the balance shaft chain, we found a small amount of copper colored shavings in there and from what I've read, it seems I may be in nerdy of a new motor soon, so I haven't drove it since, I can't afford a new/used motor so I guess I will throw my hands up in defeat :-(
The copper colored shavings are from the rod/main bearings which in this case is causing the engine rattle due to excessive bearing clearances or spun bearings. What probably happened is when the timing chain assembly started to experience breakage causing the oil pickup screen to get plugged up with debris; this resulted in restricted oil flow which caused damage to the bearings.

You may be able to salvage the engine by replacing the timing chain assembly and replacing the bad rod/main bearings.
 
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