Enigine noise on start up

Oil light is rather important it goes out if oil pressure is good comes on if oil pressure is low when it comes on damage is expected with continued operation like wearing of main bearings and pistons and cylinders can lead to a engine rebuild

would be nice to know the engine make and model to see it it has a chain or belt
could be hydraulic tappets operating until the oil pressure builds up

There are many possibilities that can cause car to make noise.

It's actually from where the noise is coming from. Front end or rear end. From engine area or from inside the steering or from brakes.

There is N-number of possibilities for the car to make rattling noise or any other kind of noise.

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For step by step troubleshooting this problem, I suggest you to refer the help link mentioned below. Its a complete solution with proper explanation to identify the cause of problem: ------

Click the link below: -----

http://alltypesofpartsreplacing.blogspot.com/2012/11/car-noisesnoisy-cargrinding.html

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These will help.

Thanks.

What you need to do is find the are that the noise is coming from. Next time you start in the morning, pop the hood first. start the car and get out and listen for the noise. Is it coming from the top or the bottom of the engine. You will have to get down to listen for the bottom. Top engine noise is usually from the lifters. They get dirty and partially collapse. They do have stuff called valve medic, thats helps clean these up. Bottom end noise Is the rod /main bearings. These can only be replaced. Basically an engine rebuild or replace.

No it isnt a knock sensor the knock sensor job is to detect a knock noise and ****** timing. The knock that it is looking for is from octane or fuel or pinging that creates N0X s. A pollution gas. The knocking noise that you are hearing is different. If it is a multiple noise ar a rattling sound that will be the valves. There are other noises like a piston knock this knock is a sharp metallic noise, If the knock occurs only on acceleration that noise is a crankshaft noise. You need to check you oil level and make sure it is corrects. Look at the oil condition do you see silverish or whitish condition,is the oil deep black.

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.

check oil pressure possible valve tapping -start vehicle and open hood if the noise is on top and sounds like metal tapping u may have a problem with a bad lifter ,oil pressure not lubing head,bent valve/push rod,loose rocker arm. if noise towards front check belts and pulleys-power steering level

If this sounds like a tin can rattle it is likely a loose heat shield on top of the catalytic converter. They come loose after time and corrosion take their toll.

Have you enough oil in it?

This may be due to old oil. I'd first try changing the oil. The viscosity of old oil may be to thin causing serious run off in the top end. All of the lubrication may be off of the valve assembly causing it to chatter and make these noises until the motor can re-lubricate the valve train.

Also, it may be due to low oil, to heavy of a wieght of oil (such as 15w40 or 20x50). I believe with most of the 04's the recommended oil weight is 5w30.

Try an oil change and see if the noise goes away. If it doesn't I'd do a quick visual inspection under the hood for rattling parts while the engine is running. It could just be a loose housing or something causing the noise. Hope this helps bud!