Hi I have a 1989 420 SEL with 340,000 miles on it. When it is cold outside, and the engine is warm it starts and purrs like a kitten. If the car sits out overnight and the temp is below 30 degrees the car starts very hard. It turns over very well, but doesn't want to fire until it has cranked about 30 seconds. Then it fires on one or two cylinders for a little bit then finally starts and runs fine. Any suggestions? Wet or dry weather doesn't seem to affect the car. Has a new battery that is the proper size and CCAs.
Thanks
Don