Valves ticking/taping/knocking when the gear in Drive position

[seto]

Hi guys, I'm facing problem with my stock 1997 XJ. The problem start when the engine was overheating 2 weeks ago coz the radiator leak. When it happen my friend was driving the car and he ignore the loud ticking/knocking/taping valves noise indicating the engine running heavy due to an overheating until the engine shut off by himself (he's stupid isn't it..). After I replace with new radiator now temperature is ok, but the valves ticking/knocking/taping noise remain coming everytime I put the gear in Drive position. Whenever I put the gear in Neutral or Parking there will be no noise, engine is normal, even when I raise the throttle it was normal on that gear position. But if I put in drive of reverse position then the noise will come and it will be getting more louder if I try to run the car fast or raise the throttle.. And yes, my car lost his power a lot.. If anyone can advice me what happened with my XJ I would appreciate, thanks..

[4.3LXJ]

Wow, this is the kind of thing I really need to hear to really diagnose it. If in neutral, and you rev it up a little does the noise come then? Does the transmission have any problems? Pull the dipsticks and smell the oil. Does it smell burned? What weight oil are you running in the engine? Lift the hood and listen while it is making noise. Is the noise coming from the top or bottom of the engine. Is is a tick or more like a thud? What part of the world are you from?

[Cheromaniac]

Whenever I put the gear in Neutral or Parking there will be no noise, engine is normal, even when I raise the throttle it was normal on that gear position. But if I put in drive of reverse position then the noise will come and it will be getting more louder if I try to run the car fast or raise the throttle.

Remove the bellhousing inspection plate and check if the bolts that hold the torque converter to the flexplate are loose.

[4.3LXJ]

Yup, that is what it sounds like.

[Mudderoy]

Remove the bellhousing inspection plate and check if the bolts that hold the torque converter to the flexplate are loose.

That's what I was thinking, but I've never heard of one being this loud.