Do you mean that upon first getting in (like morning time) you turn the key and the motor cranks and cranks and then finally starts.... but then once the motor is warm you can turn it off and it'll start right up with no problem?? If so, I've had that problem lately too. If mine sit for more than maybe 4 hours, it'll take a lil longer to start. I do know it's gonna start tho. [P] I wish I could cure that problem.
Here are some common causes for hard starts and rough idle:
The EHA/Fuel Distributor may be dirty, leaking, or not getting current:
Spark Plugs or Wires may need to be replaced.
Bad Distributor Cap and Rotor.
Vacuum Hoses cracked or leaking.
Faulty CIS Coolant Temperature Sensor.
Failed OVP Relay
Idle Control Valve.
Dirty Throttle Body.
Failed O2 Sensor.
In the classic sense if a car runs perfectly when warm/hot then that leaves the cold start system and that invariably points to the cold start regulator (my early EURO had a damper in that line as well). Possible exception is a moisture problem such that when hot the wires or cap dries out and that makes the car run fine hot, but won't start Etc.
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