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Is my car knocking, and if so, Why?!

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Old 01-15-2005, 01:28 PM
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Watch out if it is rod knock, if left unfixed, wham! Thrown rod.
Old 01-15-2005, 01:43 PM
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From the sound of what you have said, you have run your engine with a low oil level.
The knocking was probably caused by your lifters not getting pumped up.
Low oil level caused your oil pressure to drop very low. General rule is 10 psi for every 1000 rpm to maintain proper journal bearing operation.
Low oil pressure will result in metal to metal contact of bearing surfaces, instead of the bearing surfaces being separated by a film of oil.

I hope you normally wait for the engine to fully warm up before loading it up or turning any higher rpms.

You probably caused some engine damage that will result in decreased life for that engine.

I see you have attended the school of hard knocks.
Old 01-15-2005, 02:35 PM
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Thanks for the filter recommendation. I'd been using Fram filters beforehand, which I've been told is not such a good idea. I'll pick up the AC Delco this afternoon.

And yep, I keep it under 3000rpm until the engine warms up, and usually give it a minute or two at idle just in case.

Is there any way to check and tell if there is anything physically wrong with my engine, or is it just a "wait until it goes boom" thing?

Yeah, I live in the dorms at the school of hard knocks unfortunately.
Old 01-15-2005, 02:38 PM
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Thanks for the filter recommendation. I'd been using Fram filters beforehand, which I've been told is not such a good idea. I'll pick up the AC Delco this afternoon.

And yep, I keep it under 3000rpm until the engine warms up, and usually give it a minute or two at idle just in case.

Is there any way to check and tell if there is anything physically wrong with my engine, or is it just a "wait until it goes boom" thing?

Yeah, I live in the dorms at the school of hard knocks unfortunately.
Old 01-15-2005, 03:23 PM
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It shouldn't go boom.
Just a little wear.
Do a compression test. When you pull the plugs, check their condition.
It your oil level got that low, it was for a reason.
Does it leak out of seals or blow past rings or get sucked up thru the valves ?

How is your vacuum at idle. Steady or does it fluctuate?

How does the engine idle, smooth or rough?
How does the engine pull when under load before it kicks down into a lower gear?
Old 01-15-2005, 04:30 PM
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Also when you change your oil, check for oil on the oil pan. If it isn't torqued down in the proper sequance and rating, it'll leak [trust me on this, mine did until I found this magical torque sequence]. Also make sure the oil filter is on tight, and put a little oil on the rubber gasket area to also help prevent leaks. Check around the intake, see if there is any oil puddling in there. My lower intake gaskets let oil through, and I lost 1 quart /3000 miles, and when the car wasn't driven regularly, it went up considerably [I am only 14, and licenseless]. Checking the oil warm doesn't necessarly constitute the actual oil level. The oil level is best determined when most of the oil has settled to the oil pan, thus giving an accurate reading. Usually after 30-60 minutes of letting the engine sit after getting up to running temp will suffice. I usually just check it everytime before I start the car. I'm anal like that. I will dig up a pic of my intake puddle of oil. Just so you have an idea what an oil leak is like.


-justin
Old 01-15-2005, 06:47 PM
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Low oil level would also explain the pressure drop in turns. My experience with 3800s is that they use very little oil between changes (I use 10W-30 in Orlando). If you are geeting sudden serious drops in the oil level I would find out why.

Once had a oil sender blow its diaphragm and pump 5 quarts out in under ten miles on the Interstate. Was seven years and 50,000 miles ago, still runs fine.
Old 01-15-2005, 07:04 PM
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[quote][I am only 14, and licenseless]. .......Just so you have an idea what an oil leak is like.
[quote]

.
Old 01-16-2005, 12:15 AM
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It'* running normally now, it ticks VERY VERY SLIGHTLY on cold start for about a minute or so, then quiets down. I've been told it'* normal, and I'm just being paranoid at this point.

I changed the oil, it was black as night, but it didn't have any grit or obvious metal flakes on it, and the magnet on the drain plug was clean.

No loss of power, it idles smooth as silk (or as smooth as a V6 can idle). Sounds like normal. I drove it about 45 miles tonight after I changed the oil, and it performed fine.

You guys rock, I wish I could help people out more, instead of just running here when I have a problem. Thank you so much for all your advice.

Oh, and the oil pressure drop going around corners is gone now. Yeah, I guess it helps when you have oil. I feel like a complete moron, but I learned a lesson about checking fluid levels .
Old 01-16-2005, 12:26 AM
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ok try this change the oil fill with 4 quarts of oil and 1 quart on tranny fluid run it for 500-1000 miles the drain and fill normal be sure to put a new oil filter on also


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