clicking noise in passenger side dash when running

It may be the HVAC Blend Door Actuator going bad.

Thanks, any suggestions how to check that? Is it hard to get to ? Any you- tube videos you know of ?

Ya check You Tube, and yes you need to be a monkey to get at it.

Thanks again. I looked for a you tube on the issue but could not find one but if you know of one the reference would be helpful.

I found a video on the issue. These GM vans, Pontiac Trans Sport, Chev Venture or Olds Silhouette are basically all the same in those /98, /99 year models so this you tube video is very helpful I found. https://www.youtube.com/watch?v=r-clKTJuVFU

Published on Mar 8, 2013 A quick demonstration of how to access and replace the AC fresh air/recirculation blend door motor in a 1998 Pontiatc Trans Sport (also applies to other GM vans like Lumina, Venture, Silhouette, and Montana). The symptom of the problem is a loud, constant ticking noise coming from under the dashboard near the glove box.Pontiac Trans Sport Blend Door Repair https://www.youtube.com/watch?v=r-clKTJuVFU

You sound like a mechanic, lol. So is that what you have going on?

No just an old car guy who likes to try to figure out what's wrong and see if I can fix it myself. I hate getting ripped off by repair shops.A lot of the time repair shops including mfgs shops haven't a clue if the computer read out doesn't tell them what it is and even then they just start replacing stuff in the hopes it might be the solution, 100's and 100's of $'s later.That's my experience.

They should learn how to test what the code tells them what is wrong, like I do. Just because a code is set off doesn't mean what it says is what needs to be replaced.

You are right but that would take common sense but when they have generally unknowledgeable customer who trusts them and they bill the customer for their mistakes not much incentive. That's why sites like this helps the customer to be more informed as you know, knowledge is power.