Help! Loud engine noises

The car is throwing the exact codes you need. PO4 is not a viable code.

Check the oil level especially if it just got an oil change at the dealer or a jiffy lube they over fill it.

Probably throwing multiple misfires from blown bottom end of motor damage we see many of those from poor oil maintenance especially if “dealer maintained”.

What’s the history of the car did you just buy it? Or if you have owned it s long time how many times has it thrown a check engine light because it ran low on oil?

 

The check engine light blinks only for a serious misfire. You have a problem in the ignition system. Most likely a bad spark plug. Possible a failed "coil on plug" or connector at that coil, or a failing fuel injector. Again, most likely a spark plug.

Was your code a P0304? That would be cylinder 4 misfiring.

A P0420 is a catalytic converter efficiency code.

 

+1 on the engine misfire. When this happens 1 or more of the 4 cylinders of your engine are not producing power- causing shaking and reduced output. Ignition faults are at the top of the list of probable causes.

Do not wait to have this repaired- the longer you drive like this the more likely you can do permanent damage to the (very expensive) catalytic converter. A cat is supposed to cause air and fuel (hydrocarbons and carbon monoxide) to react and make H2O and CO2. That reaction also produces lots of heat. A misfire dumps a huge amount of air and fuel (HC) into the cat- it can quickly overheat and degrade or even melt internally.

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Its not wrong oil level its no oil level. Your running on a dry engine.

The red triangle is a fatal alarm its the master caution alarm the red triangle of death that means the engine ran dry and had no oil pressure. Sometimes just one of those events will toast the engine. You have had several.
Its because your car's engine is eating alot of oil and the oil level was never ever checked between oil changes.

Engine needs to be replaced.

 

I've avoided this for quite a while, but...
I have to ask....
With the information provided, your answer is seriously "the engine needs to be replaced"?

It seems like you have a serious fixation regarding everyone ruining their engines due to oil levels. At what level of oil consumption do you determine an engine needs to be replaced? Why would anyone spend thousands of dollars to replace an engine, even if it uses 1 quart of oil every 500 miles, especially if there is no smoke issues? A quart of oil is $4, and less if bought in a 5 qt container. An engine swap is $3k or so out the door, assuming a used engine, which may have more problems than the original. That's the equivalent of 750 quarts of oil purchased. 750 x 500 miles = 375,000 mile breakeven, minimum, but probably closer to 500k since there's going to be OCIs in there anyway. More likely, breakeven will never even be close to being reached. Engine replacement due to minor oil consumption is one of the most non-senible 'corrective actions' ever to enter a conversation.

 

IF the OP has damage due to running out of oil, it would likely take care of itself- seized cam, spun rod bearing, hole in the block, jumped timing chain, etc. Can't say that in 30 years of fixing cars I've ever seen low oil cause a misfire only under load. If it was a completely dead cylinder (loss of compression) the MIL would flash all the time. Checking the ignition system should be first. Replacing the engine is much further down the list.

 

Thanks for the replies! You were correct, had it repaired and she runs smooth again

Very glad to hear! Hopefully she's good for another 100k miles (other than weekly oil level checks and normal oil changes!)