Service engine soon and priming the engine

[9365turbo]

I was only running level 1. Stock on tow haul. Not sure what DTC is.

[DmaxMaverick]

DTC = Diagnostic Trouble Code: The code that will be present any time the SES lamp is lighted.
As John said, it is helpful to know the code to aid in the diagnosis.

The Edge level is not important. It must be removed to eliminate it as a cause. If it was, it wouldn't be the first time. However, if the condition and SES can be repeated, change/repair/remove only one thing at a time. If you change more than one, you won't know what was the cause.

[9365turbo]

Do I need a code reader? I removed the edge. I drove about 10 miles yesturday with it removed and the SES light came on when I parked. It wasnt on when I drove home.

[DmaxMaverick]

Yes, you need a code reader. Or, ask your local Autozone if they read codes. Many of them will do it for free.

I suggest doing nothing until the code can be retrieved. It may or may not be related to a problem you can see. If you aren't experiencing limp mode or a driveability problem, it's hard to say.

What of the "prime the system" issue? If you have an air leak, it can cause the SES lamp. In any case, get the code read. And, leave off the Edge until you get the current issue resolved. Not knowing the problem, using it may be damaging.

[9365turbo]

I will leave the edge off. Will there be a trouble code if the light stays off? The truck has no driveability problems.

[DmaxMaverick]

The code will be in memory for several start and/or warm-up cycles depending on the code, but not indefinitely. Check as soon as you can. You may find more than one code, as not all of them will command the MIL.