Not sure if this is considered low or normal BUT .. my engine idles at about 400-500. And if the AC is on it drops a tad more. Sometimes it feels like it drops enough that the engine may stall. I have even started it, let it sit for a moment, put it in reverse and the engine died .. Cranked it back up and went on my way but why would the engine die?

Should I increase my idle to about 700-800, if so how do I do this? I remember on an older GMC, 80's, you could just adjust a screw .. I don't think you can do that now. Is there a reasonable inexpensive way to DIY this? Thanks!

 

I have a 99' and I'm pretty sure your year has a computer onboard like mine that controls/adjusts the idle.....it's not something you can manually adjust. A dirty throttle body will cause a low idle.

Have you cleaned your throttle body? Here's a video on how Clean the throttle body on 95' to 99' models. Should be similar for your year. Do a search on you tube for Details for your year. Hope this helps you out.

 

Probably fuel pressure regulator. I had the same issue with a 2000 5.3 suburban

 

You may want to check your Idle Air Control valve.....if the throttle body is dirty sometimes the opening for the IAC valve can get carbon build up and needs to be cleaned to work properly. You may also want to check it to make sure it is working. There are videos on YouTube that will show you how to clean, test and replace if necessary. Hope this helps you out.

 

Could be throttle position sensor as well, I had one bad and wouldnt idle had to hold brake and apply gas at a stop. Just another possibility. The real problem is all the sensors on vehicles now. What ever happened to fuel fire and compression to make an engine run?

 

Thanks everyone. I will check all these out and see how it goes!!