New member here, hi.

I have a 2001 sl1 that we've had for 10 years and we're just now having problems with it.

i was driving home two weeks ago and it stalled with no warning and the battery and oil light came on.

i tried turning it back on and all it gave out was a screeching noise. wont start anymore. we had the starter tested, came back with no problems. checked the timing chain, which was fine. the crankshaft position sensor and the fuses were all fine. We charged the battery.

when the PCV valve was taken off and cleaned, it started back up, but with an awful knocking coming from the engine and a high idle. i don't want to screw up the engine any further by trying to run it like that.

any thoughts?

 

I'd be planning on taking a weekend to disassemble that engine -- your description suggests major problems...

 

Major vacuum leak and ran it out of oil?

 

This really requires a hands on, or eyes on for troubleshooting, it could be a lot of things. I think the first thing I would do based on your information is remove the valve cover and check for a broke rocker arm.

Next, slowly rotate the engine to top dead center TDC using the marks on the harmonic balancer/front pulley. The look at the rockers for the #1 and #4 cylinders. One of them should have the valves completely closed, the other should have both open but just slightly. If both valves on #1 are closed and #4 partly open, the exhaust valve on #2 should be fully open. If 4 is closed and 1 party open, then 3 exhaust should be fully open.

The reason for checking this is that the key on the crank pulley could have sheared. There would be a lot of friction though so the crank and cam would both turn, just not in sync. This would cause the screeching sound and allowing the engine to run for short periods of time as the cam and crank got close enough to sync to run.

Another possible cause of your symptoms would be a broken flex plate if you have an automatic transmission.