I have a 2007 Infinity FX35 with cold starting issues. Every morning the car doesn't want to start, takes several times of cranking on it to get it started. When it does finally start it has RPM variance for a few seconds. The car runs great the rest of the day. I've had it to three different name brand shops and they can't find out what the problem is even though it does the same thing to them. Got any ideas?