1987 Nissan Pulsar question

I have a 1987 Nissan Pulsar, 1.6 liter, twin cam, CD16 I do belive ( fuel injection)

Anyways here is the current problem.

Until its warm ( been running 10-15 mins ) it will idle about 1000 rpm, and now rev up as fast as it should on acceleration. Once the engine is warm however, it will idle at 1700 rpm, and run perfect.

I changed the MAF sensor, and this helped out considerably from how it was running before. But still there is some sort of Temperature switch or soemthing i need to change?

Also note I put in a used MAF sensor.
:?