Sluggish cranking - especially when cold

My friend has an '86 Legend 2.5L V6. The first time it is started in the morning it has to crank for several seconds... then runs fine. Once it is warm it cranks up with a bump of the key. If left to sit for say about 10 minutes... it may take a few seconds to crank up again. It has never failed to start. We replaced the Coolant Temperature Sensor and it still does the same. The ECU flashed a code 12, which is EGR, but once it was reset, has not come back. Any suggestions? Thanks in advance.