I've been getting P1071,P1074,P0300 off and on since I moved to Colorado from Florida 2 years ago on my 2001 Suburban 1500. the codes go away and come back, usually when it's really cold out. A mechanic told me it was no big deal so I've let it go on, still checking the codes every time I get a check engine light.

2 days ago, the truck is misfiring bad, rattling engine etc. It pulls the codes P1071,P1074,P0300 but with an additional P0200 indicating the injector circuit was not doing good. Paid a shop for a diagnostic, they pinpointed to ignition coil #4 shorting to ground. I installed a new one, the truck seems to run fine again so I clear the codes.

Today I get the check engine light again but it seems to run normally. This time codes pull P1071,P1074,P0300 with the additional U1000 and U1016. "Class 2 communications failure".

Any ideas what I'm dealing with here? Is this worth diving into?

I just want my truck to run right. It already needs so many things for the suspension & steering I've been planning to do. Now the list is growing, its at 225k miles and I'm kind of attached to it. Already put a rebuilt transmission in it and so much more has been put it into maintaining it. I'm starting to wonder if I should part ways with it as it's becoming a time, money and energy pit. Would love to hear your thoughts! Thanks