The issue that I'm having right now started about a month ago and for a whole month I've been trying to figure it out. First it had erratic RPM then at the same time the temperature gauge would not read and the ABS in a slip light comes on. Hard to start up and the codes that it was running it went away then the truck started shaking real bad which was caused due to misfire on cylinder 7 I fixed that then the truck started running perfectly yesterday then this morning it's like it started all over again with the same issue. Not reading the temp, erratic RPM, and the ABS and slip light is on. I don't know if it's a major electrical issue but I really do not want to spend money taking it to a shop to diagnose it. I was hoping that somebody on here might have gone through the same issue that might be able to enlighten me.