1999 Gmc Sierra Test Replace Fuel Injectors Could You Give Guide Lines

We need a better explanation of what your problem is and what you are trying to find out.

I was told they needed to be changed but wondered if there was a way to test them and make sure they are bad. they cost so much that I am hoping all they need is to be cleaned instead.

Again................... what is the problem with the truck?

the right side is burning more gas then the left and when starting it idles fast. Idle is also not even jumps around.

I am trying to help my disabled neighbor. So I will have to call and get more information if needed. Thanks for the assistance so far.

How did you conclude that one side is burning more gas than the other?

He said he had a mechanic look at it. It's just the mech around here have been known to cheat people so bad that he asked me to check into it.

You need to get this diagnosed properly. It's rare to have even one injector go bad and unheard of for all of them. You may have a totally different issue.

If it's the drivers side getting loaded up, then you are likely looking at a bad regulator. Much more common. Either way, the upper intake has to come off.
Any gtech that knows what he's doing could easily diagnose this.

They just said something about a spider being cracked

First of all, what engine does it have?