99 K1500 Suburban 5.7L
115K

Hey guys, I was driving along today and I noticed that the SES light turned on. It was not flashing, but instead it was steady. I consulted the manual and it listed a few causes including a loose fuel cap and emission control system problems. The truck was just inspected this past June. I know the fuel cap isn't it, but does it necessarily mean my emissions control system is going?

I don't have access to a code scanner until this weekend but will need to be driving every day until then. Can I hurt my truck by driving it?

Things of note:
-I put 89 in it instead of 87. Could this be screwing things up?
-she idles a TINY BIT rough. It's not really that noticeable but is still noticeable nonetheless. Goes away when throttle is applied. Is 600-700 RPM a normal idle range for it?

 

Higher octane won't cause this, will lighten your wallet tho.

Plug wires can cause a rough idle. Make sure they are all connected properly.

Most auto parts stores will scan for free.

 

You might also try a 2-3 bottles of Techron in a tank of gas and see if the roughness improves.

 

Hi
I have a 1999 Chevy Suburban K1500 the Service Engine Soon Light came on and stayed on the whole I was driving home and what causes the Service Engine Soon Light come on?

 

Don't wanna high jack a jack a thread , but how do you post a new post just got on this site