Variable value on the end of the cam shaft

[Jim19460]

I am looking for advise because after speaking to several mechanics I have been told different things. 

I own a 1999 Lexus ES350 with a 3.5L engine. The motor was making a tapping noise to I took it to my mechanic to see why.

He advised me it was the Variable value at the end of the cam shift. To replace it would cost about $4000.00 and was not worth it.

The car runs well other than the noise. His advice was to continue to run the car as is it will not damage anything. I looked it up on the internet and YouTube and see where some say to have the car repaired and others say it won't hurt anything. What do you guys suggest? The car only has 88000 miles on it. 

Thank you in advance 

 

[RX400h]

It could be in need of valve adjustments:
How do I quiet the knocking noise in the engine of my 1998 Lexus ES300? I was using the wrong fuel in the car for months (justanswer.com)

Is your mechanic a dealership technician? If not, you may want to have it inspected at a dealership (Lexus or Toyota) since it is more likely that someone there has run into the same scenario.