Is it possible for lifters to click / tick, but only under load?
Im asking, since i have a clicking / ticking that is fairly noisy when I am driving along, most noticible when accelerating, but it seems to be there all the time.
When I am parked, and have my head under the hood, I cannot duplicate the sound, no matter how i rev the motor. Otherwise the car is running fine.
It wasnt there on the way to work on tuesday, and on the way home I heard it.
No oil consumption before or after (just a tiny headgasket leak that has been around for 1.5yrs. Im not even adding oil between changes.
I am significantly overdue for an oil change, but I cannot see how this would do anything.
Ive tried the "mexican tune-up", with no success

Is there some way maybe to unstick a lifter (if thats even it?)
Car is a 91 Jetta 1.6td
Thanks for the advice..