car wont start

:eek: we put it on the computer and it gave code 43 cps my boyfriend changed it and then it would not fire not getting spark. people are telling me that its the ecm could that be the problem? we have now changed the ecm it was burnt and it still wont fire getting plenty of gas and now it iis spittin out code 21 tps the starter does turn over no spark to the plugs we are just plane lost

We need more information!
1) Does the starter turn the engine over?
2) Do you have spark to the plugs?
3) Do you have fuel pressure?
4) Was it running and quit on the road, or did it just not start when you first tried?

Give as much detail as possible!

Could be any number of things.
You need engine cranking and good hot blue spark and fuel pressure and injector pulse and compression to start it.
Do you have any of these?
MT