The engine is the same, but somehow the engine head is different in Swift, the coils issue is on CNG due to less current. If it wants to be a pain, the coils might die after every 10-20k kms, if not they might last a gud 100,000kms.
On Petrol there just fine. The issue comes in when CNG is involved, my Liana coils (1 died at 18k kms and the second one died at 23k kms, CNG injector died at 24k kms sold the car at 25k kms