Engine noise... rod knock?

[randyinlosangeles]

I have a 1990 Q45, 146,000 miles, car hasn't been run much lately, as it hasn't passed smog (needs a MAS and 3 injectors) Lately, when starting the starter would bind up, and I would have to hit the key repeatedly to get it to turn over, I was going to replace the starter this weekend, when I started the car, after it had sat for a week, it turned over a half turn then with a BAM! quit turning over. The battery was low, so I took it out and had it charged up. The car started, but now there is a loud metallic noise coming from the engine. It doesn't sound like a Rod, it's not that 'heavy' a sound (I've had lots of rods go, I know what they usuallly sound like, but maybe this is a rod knock with a japanese accent?) Is there something in the valve train that can let go? It doesn't sound like a lifter, way too loud and heavy for that. I'm afraid to run the car, in case what ever is wrong is possibly minor (yeah right) and I'll really mess it up by running it, but it has to be moved every 3 days for parking regs. Any thoughts on what this could be? I can do any mechanical repair, but I'm just not sure I want to tear into this engine. As I was going to sell the car after changing the starter, I really don't want to sink a ton of money into this, but will probably wind up selling it as a parts car if the motor is shot.

[911/Q45]

Most likely broken chain guides. Do a search on this and you'll learn more than you want to.