I own a MK1 leon 90 evertime I rag it to 4k rpm in 4th gear is goes into limp mode, the turbo is 100% it's mapped but the engine I had in it previously didn't go into limp mode it boiled and swapped a new one, all the vacuums are ok, no boost leaks anywhere injector wire 3 is spliced but tested and works, could it be the actuator? Although it's holding boost fine I 3rd to redline. Another Symptom when booting in an hour ago in 3rd gear is started spluttering and some white smoke came out and the car stalled I let it roll on and it fired up again.