The other day I was driving my 88, it was driving beautifully as usual, it was hot out so the A/C was on, top down around town driving to about 45 or so. all of a sudden I'm hearing a rhythmic banging, almost like a piece of metal being stuck in a fan ( similar to when kids used to put a baseball card in the spoke of their bikes for the sound) there were no codes, engine not running any hotter, kept going even when the A/c compressor was turned off. I stopped the car, and immediately checked under the hood, the noise seems to come from the front of the engine( passenger side of car) but really cant tell, I took the belt off and tried to turn all the pulleys and discovered that the smog pump did make some noise, so I replaced it but I still have the noise.. no codes, no running hot.. so now I'm trying to figure out how to see if the problem is internal, or just a component going south ( like the water pump)

would it hurt to run the car a moment with the belt off to see if the noise continues?
Any suggestions appreciated.

Thanks, Matt

Ok, just removed the belt and started the car, and no noise.. so YIPEEE!! it is external, since the air pump is new, the alternater is newISH, and the power steering pump, and belt tensioner seems to be quiet when turned by hand, here's hoping it's the Water pump and not the A/C compressor!!