well..... I would say two things first off.
1. remaps are good and do benefit the engine (due to egr and dpf removal) and improve economy and power
2. remaps don't fix faults; they never can and never will. At best they hide faults. For future reference you shouldn't remap a car that has problems, as it can hinder the remap process. A true remap will download and edit the current map on your car so it is customised to your car - places that turn up in a van and just flash something else onto your car are not tailoring the map to your vehicle and should be avoided.
If there are issues with your car then your engine will not be running at optimum and therefore your remap is not based on optimum, but never mind....
Out of interest who did your map? you should usually take it to someone who have good reviews and experience of mapping these cars and engines - Gus @ Alfatune is well known around these parts and does great work. There are some mappers out there who are known to cause problems.
It wouldn't surprise me if you're actually hitting overboost to be honest, but as Kid says, the only way to know for sure is to get yourself the fault codes read. Most simple way to do this is to buy yourself an ELM or KKL cable off ebay (around £10 ~ £15) and use the free version of FiatECUScan (now known as MultiECUScan). This does of course require a laptop.
This will give you a lifetime of troubleshooting and fault finding abilities for a small single outlay. Go for the ELM cable if you can as this is capable of more.
There are 3 levels of fault codes that the car will have.
level 1 is the lowest level of code and this will be generated and stored in the ECU's memory but the driver won't be alerted to the fact it is there as the error is only very minor.
level 2 will produce a code and a warning on the dash but limp mode is not activated. this is a fault that is serious enough to need more immediate attention from the driver but there is no immediate risk to the engine but will need sorting as soon as possible.
level 3 is the top dog and will give engine light and limp mode - this is something that means the ECU has detected a fault that could pose an immediate risk to the engine if it continues so the engine is put into a reserved mode that allows the drive to find a safe place to stop and seek attention and something that needs fixing right away before more serious harm is caused.
Limp mode is only activated when a fault is detected - the fault will remain logged until cleared, but if it does not present itself in the next 7 engine start / stops it will remove the warning light. However if when driving the ECU detects the same problem again you'll get another limp mode. The ECU assumes after the engine is stopped that the fault has been fixed but the codes not cleared and so will proceed assuming all is well until it discovers otherwise.
Good look with your fault finding - MultiECUScan usually gives good fault code descriptions so you should have a fair idea after reading the codes.