replaced parts on 1991 ford explorer,why still hard to start?

[Carolyn]

1991 ford explorer,very very hard to start,replaced eec relay,fuel relay,the fuel pump comes on,replaced spark plugs,replaced idle contro valve,replaced map sense,replaced fuel filter,but still very hard to start,runs fine after start,so whats the problem?

 

[Silverstang]

Replace the spark plug wires?

 

[SVOMAN]

check the trouble codes, especially for the cold start circuit..