It is possible for a 119 motor chain to slip a tooth or two, it happened to me. The upper guides had shattered and were not functioning. The chain was loose enough to slap the bottom of the valve cover, which was probably happening on start up before the tensioner had built up pressure. It is a very difficult thing to diagnose as it throws off no fault codes. The car just doesn't run well - it idles poorly and lacks power. Thinking I was looking for one bad cylinder I tried pulling spark plug wires to look for a change in idle. But there were several cylinders that without spark had no impact on the idle. I don't know if the chain had slipped one tooth or two but there was no damage to the engine. The car has been fine ever since getting a new chain and tensioner. The only way to find the problem was to remove the valve covers. I wouldn't think you'd want to consider the car without doing at least that much.