Stolen and recovered - engine noise?
 

Long story short, my 98 EX coupe was stolen, stripped of all aftermarket parts (I/E, rims, audio) and abandoned on an interstate. Basically, whoever stole it took it somewhere, stripped it, and drove it without the intake or exhaust (the header was still installed) and left it somewhere. I don't know how far it was driven without these parts, but I know it can't be good for the engine. Luckily enough, I got the car back and reinstalled the stock parts which I had wisely kept.

Everything seemed to be running fine after installing the stock exhaust and my old AEM short ram I had laying around, so I drove it on a 200 mile trip without noticing any problems. Then today, I started it up and heard an unusual sound at idle. I checked my oil and had to add a quart, but the sound didn't go away. After driving for about 10 miles or so, I think the sound went away and my oil level was still full.
A few things to add: the temperature was in the 40's today. I have had a slow oil leak, but I only have had to add a few ounces every month or so for the past few months. The motor has about 150k miles on it.

Does anybody know what could be wrong, or if anything is really wrong with the engine? I had been planning to install a turbo kit using the insurance money since I was able to get the car safely on the road again for little money using my stock parts. Will I still be able to boost my engine without additional problems?

Thanks for reading all of this and I appreciate any input you can give.

that really sucks man, gl with building it back up and I think you should b fine where you in elevation?

thanks. I'm not in mountains or anything, what do you mean by asking?

Maybe the low oil caused some loud valve tap until the oil warmed and circulated to the top of the engine. What weight oil are you using? Where is the engine losing oil?

I am using (Valvoline conventional) 5W-30, which is the recommended weight. I think the oil is leaking through the oil pan and I probably need to get a new oil pan gasket..

Could the sound have anything to do with running the engine without an intake or filter as well?

It's important to fix the oil leak. Try to localize it by cleaning off the old oil from the engine and then watching for the location of fresh oil. Could be coming from the oil pan, but other common oil leak locations are the front or rear main seal, the distributor, and the valve cover.

It's possible, but the low oil and cold weather seem more likely.

I am leaning towards the oil pan because the oil gunk is mostly on the outside of the oil pan, but I'll probably use the clean and watch method too to make sure.

Would you recommend switching to synthetic oil after I fix the leak? I am also planning to boost pretty soon, if that makes a difference.

You can't go wrong with full synthetic motor oil. The boost gurus should be able to answer the other question.

I really hope the only problem is the oil leak. Thanks for the help, RonJ.

just cut off my ac belt and it got rid of my odd noise. ;)
i asume the tension pulley is getting dry or the compressor im not positive yet. im gonna replace taht tension pulley when i get the ac fixed. it doesnt work so i just cut the belt to experiment. and luckely it was the right and my noise went away for now ;)