04 Emission Light

[RLV]

All of a sudden I have this yellow engine symbol light that is staring at me on the dash...Just as I was calling the dealer to make an appointment. It went away, only to come back again a day or two later.

No performance issue w/the truck. Any Clues ?

[GrampyJim]

The 6.0 is one of the most complex powerplants on the roads today. There are many concerns that can turn on the Check Engine Light - most are based on turbocharger system performance though the turbo may or may not be the root cause.

Without reading the code(s) and performing the appropriate diagnostics, there's really not much to be done.

[MikeL46]

I've had 4 different causes of the Check Engine Light:

- EGR valve sticking

- Overfilled fuel tank (filling after the pump shuts off)

- Turbo failure

- Injector failure

The only one that cured itself was the overfilled fuel tank. After about 50 miles the light would come on. After another 100-150 miles the light would go off.

The others all set codes and needed a tech to repair.

Mike

[OT]

Just got back from 1600mi. rtrip. Towing 5X8' uhaul loaded w/beds etc. so really not much wt. Punched it/shifted down & passed on long uphill grade, 6%? but punched again cause traffic catching up before I could get over. Did make black smoke both times.

Noticed Ck. e. light (emission) was on, but only noticed after top of hill. E. seemed to run ok, but kinda felt like power down alittle? Like that for last 100mi.(one way) of trip. Made appt. to take in, however 2 days before appt. light went off. Test runs flat/uphill (solo) e.power seemed normal. Oil/water etc OK. I was thinking maybe egr didnt like all the smoke (soot) its still oem @ 21K. [img]/ubbthreads/images/graemlins/shrug.gif[/img] Didnt take in.

Return trip (630mi solo) e/power normal, mpg ok, no light. Long day, left 5 am/home 7pm. So....

Q...Just to clarify, yours no power loss etc, just e. light, right? TIA