Code 4, Crank Angle, Bearing colors/sizes

I ran into a little problem recently. Pulled up to a light, pushed in my clutch and my rpms dropped like they normally do, however, it started to stumble and I had no power what-so-ever. It started throwing code 4 which is the crank angle sensor. I got home and noticed I was low on oil, and it looks a little on the metalic side(it was dark when I was looking), so I filled the oil back up to the normal level. the timing looked good on the mechanical side. I probed my distributor sensors to see if one was haywire but all checked out ok. I took my distributor cap off and noticed my ign. rotor had came loose from the metal housing it’s made onto. I got a new distributor, installed it, and still no luck. Still metal on metal sound and still the code. I can turn the car off then back on, and the code clears but it seems like when I go lower than a 1,000 rpms it throws the code again and it dies. I had a bent piston to replace around 200,000 miles and when doing so I also replaced all piston bearings and put in new rings. I’m at 255,000 miles now. I did a dry compression check and they range from 175-184 psi. Which from my understanding is good. When I replaced my rings and bearings I noticed that the piston bearings were looking pretty shotty and would obviously think that my main bearings are starting to get there as well. I have also not noticed an oil indicator light coming on, and have not checked my oil pressure, so I’m not sure if my oil pump could be causing an issue, and the lack of lubrication making all the noise.

When going to the Acura dealership to get new parts for the semi-rebuild the only question I remember being asked was if I bored out the cylinder and would be needing oversized rings. I declined, since I was only going to rehone them. Now that I’m in the process of maybe looking for new main bearings/thrust washers I see that they have different colors and variations to the bearings sizes. I usually stay with Honda/Acura parts for internals on the bottom end side of things but just out of curiousity I took a look online and can find just a set of main bearings, no colors, just a standard size. I understand that it’s important to get the right tolerences as to not mess stuff up. And I know it’s just a matter of me getting off my butt and pulling apart my car to find the exact information I will be needing/whats causing the problem. However, I am curious if in my process of rebuilding at 200k did I ruin my piston bearings or am I just looking at getting new main bearings due to age/possibly low oil over years/what-not? I am also curious as to where I could find color codes for the vehicle or if I have to plastigage each bearing seperately(maybe top and bottom I’ve read)? Or if anybody has any information as to why I would be throwing a code 4 other than the bottom end being toast, maybe something on the transmission side? I should also note that other than small various problems we all encouter with these cars (idle issues/iac/fast idle, etc…) the overall performance and feel of the engine has been great even since my little mishap at 200k. P.S. I do know it is shotty not to pull the whole thing out and rebuild buut time issues.

Update… Loose cam gears. I put in AEM’s last I did my timing belt a couple months ago. I thought I tightened them but must’ve just snugged them up. I also found the general location of the colors.