Xr3i cold start fault

[Xr3i-joe]

hi guys just bought a xr3i the problem I can't get to the bottom of is when you first start it it will cut out and then start again and so on for 5 mins until walms up and misfires until at normal temperature (I think as temp gauge also doesn't work but changed the sensor?)

im stumped, pulled cold start injector out and that squirts when you turn the key changed plugs and fuel filter. Before I bought it the previous owner said it would boil over but he changed thermostat and has not since. The gauge and fan does not kick in so not sure what temp it's running but it does not boil over now. 

Any ideas guys? Cars going into paint shop  next week hoping to have engine sorted and not ready for summer