I thought they did all that basic testing. The ECM harness has two small ground wires that terminate on the rear bellhousing mount studs, they are twisted together into a common 3/8 ring terminal. The studs are on each side of the bellhousing where the curve transitions to straight down. They are fairly small guage wires and the ring terminal is steel and could corrode. Check these to see if they are loose on the stud, there may be a negative battery cable over them on the stud. If there is signs of corrosion inspect them carefully for continuity. The ECM circuit grounds through these small wires. Good luck.

Pull your timing chain cover off and check for wear, like was said it may have jumped. How many hours are on the engine?

ill have to check this tomorrow, thank you so much every one for your help, ill for sure let everyone know when i fix it and what it was.