Multiple Diagnositc Trouble Codes

[waterman]

Hello,

2015 Yukon Denali. Friday night my truck had a very bad vibration at idle, car drove fine on highway. I had car towed to Chevy gmc dealer and here are the codes:

P0300,p0307,p0308,0401,p0301. Plugs have been changed. Dealer said back cylinders are misfiring and two injectors are bad and there were problems with two others. They ordered parts yesterday and they called me today and said there wasn’t anything problem is still there and that are waiting to hear from tech support. I am 175 miles from home, car is 23 miles from me and I will be missing my third day of work.

Any suggestions on what is happening?

 

[waterman]

Sorry, 60,000 miles

 

[Doubeleive]

Probably something electrical and the dealer probably already said the same, all we could do is guess from 10000 miles away

 

[RoadTrip]

It could be electrical, such as the internal corrosion problem in the negative battery cable; it could be corroded grounding points; or it could be that your valve lifters collapsed on those cylinders.

 

[waterman]

Thank you for your replies.

 

[jaxscuby]

P0300, 0301, 0307, 0308 misfires, and specific cylinders

P0401 EGR..Clean or replace the EGR valve: If carbon buildup or clogging is found, clean the EGR valve and replace it if necessary. Clear blockages in EGR passages: Remove carbon deposits or debris from EGR passages to restore proper flow.