I have a 1992 GL and about a week or two I noticed two noises that the engine was making. One sound like clicking, at a pretty fast rate like I don't know maybe 10 clicks a second or something. The other noise sounds like rocks tumbling around. I took it to a mechanic for a free estimate and I don't even think he really looked at the car but he said it was bad valves and that it would cost $1500-$2000. I'm going to take it to another mechanic to get a second opinion but has this happened to anyone here?