Noticed my EGT Temps are erratic in my 93 HDJ81. Probe (type K thermocouple) is in exhaust manifold, pre-turbo. I've been troubleshooting this issue for awhile. With my thermocouple wire disconnected from connector leading to inside the cabin, I measured the mV at connector coming from EGT probe. Voltage is steady and makes since with normal exhaust Temps BUT when you roll front windows up or down the mV noticeably fluctuates. The type k wire is not run near other electrical wires while I was testing. I'm picking up electrical noise somehow.....my next thought is block grounding issue. Thoughts?