Hey guys, so I just swapped out the 380, 000 km 5.3 L on my truck with a used 130, 000K. Did a really smooth in and out, no wrestling or hurting anything. I disconnected every sensor and switch that runs from the fuse block down across the front rad support and then around to the passenger side o2 sensors, and gently hung it over the drivers side fender for the work. Also had everything labelled where I got it from.

Put everything back in and together, engine fired up first try, runs absolutely gremlin free. What I'm left with is an issue that includes my signal lights, cruise control and 4WD controller.

Start truck, sometime says service 4wd, sometimes doesn't. When it does, the little yellow light on the push button 4wd is not indicating what range its in, and it will no shift ranges. Other times the 4wd works fine.

At no time, driving or stopped, will the cruise control work.

When stopped, idling, not in gear, signal lights works. As soon as I started driving the truck, once the rpms get above about 1000, the blinker will speed up, then cut out and not function again until I slow down almost to a stop.

Any ideas? I suspect one of the ground faulty. I understand that there are grounds for different harnesses. The ground for the front lighting harness is on the frame below the rad support. It's fresh metal to metal and is good. What my Chilton manual will not tell me is what ground location the different wiring harnesses use. So I know that the Vehicle Speed Sensor and the Cruise Control are in the same harness, but I don't know which ground location they use, and I think this could be the one.

For the time being I'll keep digging, if anyone has had this problem or similar, Id love to hear your thoughts.

 

is it possible that some wiring was smashed when you dropped the engine in? check very carefully for loose grounds, especially the grounding straps for the engine block