What boost have you it running on? My engine light used to pop on after full boost but found out that it was my speed sensor on the gearbox it wasn't connected, get some copper wire with insulation still on it strip off both ends so you have two copper ends and bridge TE1 and E1 in your diagnostics port and have someone look at the engine light on your dash and count the flashes, there'll be a series of flashes then a pause then another series of flashes for example 3 flashes and a pause then 2 flashes will mean the code is 32, that should give you your fault code for the engine light mate