Im tuning a 99 Jeep XJ with a 6.0l LS engine swap, 36lb injectors, 90mm DBC throttle, mild cam and th400 tranny. I calibrated MAP and adjusted all thats needed to get it idiling and running good. No MAF. I set the rev limiter at 7000rmp and Resum at 6995rpm. Part throttle and before hitting rev limiter all runs great. No more than 3% error on MAP table, good timing, no knock. As soon as I hit rev limiter, engine dies. Fuel doesnt resum at the 6995rpm set point. I checked the tune, but cant find anything missing. I ran the scanner, but it all looks good until it hits 7000rpm. Im using HP Tuners. I have tuned multiple vehicles similar to this one with no issues like this. ECU is a Stock 411 Gm. Any ideas what might cause the engine to die? Can the ECU be bad amd cause this issue and still run great everywhere else?