Check engine light mystery

[lashout7.3]

so i just bought my first powerstroke. a 2001 f250 7.3. and the day before i picked it up there was no CEL. but the day i got it there was. the dealer said its probably nothing probably and evap sensor. i couldnt hear anything wrong in the way the truck was running so i bought the tale. the light is still on even after i erased the codes with an OBDII scanner twice. it keeps comming back. im not sure of the code but it keeps comming up as cylnders 2 4 6 8 glow plug circuit. no missfire codes or anything. theres not a whole mess of white smoke on a cold start so im fairly sure ( assuming and all that ) that my plugs are ok. it only smokes white litterally as you start it then it goes clear. no missing no problems with power. does anybody have any idea what might be causing the light?

[SuperCrutyPS]

This could be a result of an issue with the UVCH (under valve cover harness). Many have reported that the harness is A) Not plugged in securely or B) faulty. Since all the GPs on the same bank are reporting the error, this points there. It's worth taking a look at it.

[lashout7.3]

now. at the risk of sounding young and inexperienced... how would one go about doing that

[woodnthings8]

You have a California truck and have a Glow Plug Control Module (GPCM). Sounds like it either has a loose connection or it is bad. The GPCM is mounted on the passenger side valve cover. You will have to check it out. The part is around $150, so I would go to the dealer and ask them to refund you the price if it is bad. You have a diesel so no EVAP sensor.....