Check engine codes

[Waterloo]

How many miles?

If you are going to own and keep this truck, you will need an Inline Reader and Insite. Check eBay, search for Inline 6, they have the kits from $200 on up with everything you need. Get one.

I have that large monitor screen in mine that gives all of the diagnostic codes, but on yours, if you do not have that 5 inch screen, I would think the codes would show up when you turn the key on, or when you start the truck on the odometer screen.

Which light is going off? One of the triangles or the actual check engine light?

Is the truck still mandated or has it been deleted? Ever perform an EGR tuneup? How about that fuel pump? Do you know if that has been rebuilt or replaced? Overhead? If still mandated, cans been off to bake and de-ash? How about the SCR system, ever been serviced?

There is an unfortunate amount of maintenance on these EPA trucks, quite a bit, to the point of ridiculous in some cases. You really need to step up and learn the systems along with purchasing the proper tools to maintain one, and a willingness to get your hands dirty. You found the right spot to be if you are up to the task of listening and doing for yourself.