Date: 201310
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Dawn
Aircraft: Cessna 400
Operator: Personal
Operating under: Part 91
Flight plan: IFR
Mission: Personal
Flight phase: Initial Climb
Airspace: Class E ZZZ
ATC / advisory: Center ZZZ
Reporter organization: Personal
Reporter function: Pilot Flying; Single Pilot
Reporter qualification: Flight Crew Private; Flight Crew Instrument
Human factors: Workload; Distraction; Confusion; Communication Breakdown
Anomaly: Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Detector: Automation Aircraft Other Automation; Person Air Traffic Control
When detected: In-flight
Result: Flight Crew Took Evasive Action; General Maintenance Action
Contributing factors: Procedure; Human Factors; Aircraft
Primary problem: Ambiguous

Narrative: I am a mid-50's private pilot for the past 10-plus years with an instrument rating; with roughly 1;465 total hours to date (roughly 300 night hours; 140 instrument; 100 simulated). On a flight that began early yesterday morning; I filed an instrument flight plan to leave at sunrise to fly to a southwestern airport. I got to the airport at early when the FBO opened; prepared for the flight; performed my preflight and run-up; and got my clearance from ATC. In that clearance I was told to fly to a VOR via the departure; then direct (I believe it was direct after that); maintain 9;000 FT; Departure frequency was XXX.XX; and squawk XXXX. I repeated this back to the Controller; and he clarified something to the effect of that he would turn me or that I would be turned prior to reaching the VOR. At that point I misunderstood and though that I was to head instead to the VOR and that he (or someone) would provide me radar vectors to turn to prior to my reaching it. I of COURSE in retrospect should have simply inquired and asked outright; 'so do you want me to take the departure or do I go to the VOR and you will turn me before I get there'; but I just didn't do so. In any case; a few minutes later; I again contacted ATC and informed him that rather than get my final release from him; as the Tower would be opening in a few minutes; as a courtesy; I would wait for them to open and get my release from them; which he acknowledged.The Tower then shortly opened; and he immediately provided me my release. It was VMC at that time; and although it was not bright sunlight at all yet it was exceedingly clear and easy to see by the light of the pending sunlight. I flew direct to the VOR and as I started to get close to shore and the mountains they held (although I was already higher than the highest point of the mountains there; being above 8;000 FT at the time) and was about to contact ATC I was contacted by them and asked if I was on the departure or direct the VOR. I explained that I was direct the VOR; and he replied that I should be on the Departure and that I should execute an immediate left turn to I think it was 180 degrees (after he confirmed that I could provide my own obstacle avoidance; which I could easily and readily do). A few minutes later he then again contacted me and directed me to call upon landing for a possible deviation (which I did immediately upon landing before even leaving the cockpit as soon as I shut down the plane).As an aside; on that same flight a few minutes later still in the climb with the cabin heat on full; the Carbon Monoxide Alarm (both visual and auditory) in my G1000 went off. I was already wearing oxygen (as I was planning cruise flight at 17;000 FT) so I turned it on full; opened all the vents; and as I was looking for an airport to urgently or; if needed; emergency divert to; the alarm stopped and the red notice disappeared after no more than 60 to 90 seconds. (We had had difficulty with carbon monoxide in this airplane in 2010/2011 and it was finally successfully identified and fixed/repaired at that time; but as a result of my prior repeated carbon monoxide exposure experiences in that plane until it was finally fixed; I immediately knew what to do.) I tried counting serial sevens (a habit I started LONG ago as a pilot in addition to wearing my pulse ox to ensure adequate oxygenation was to continually and repeatedly subtract serial sevens in my head from a randomly chosen five digit number to ensure that I am alert and 'sharp'; especially when I am at altitude/in the flight levels - just as a means of double checking and ensuring my oxygenation status) and found that I had some difficulty doing them (which of course I normally would not have any difficulty executing at all). Whether this was because I was hindered by true relative hypoxia and carbon monoxide exposure or; perhaps the stress of the alarm going off I simply cannot say; I'm afraid. In retrospective review of the events; I clearlyshould have asked for clarification of the clearance if I had any question as to his intent; which I did; yet I did not ask for clarification and this was my mistake and mine alone. At all times the Controller was exceedingly proper and professional and helpful; and this misunderstanding was entirely my own fault. I would love to blame it on being tired; but I had a wonderful night's sleep the night before. I would love to blame it on the Controller; but he was clear and precise and I simply misunderstood. I would love to blame my not thinking clearly and not simply asking for clarification as I normally would and should have done on carbon monoxide exposure; but there is no way that I know for sure that that was the case (I have of course hours ago already requested our A&P to investigate the carbon monoxide issue). Clearly; the learning point here is a) be certain that you fully understand the provided clearance; don't just 'read it back'; and b) if you are not sure; ASK.

Callback: The Reporter stated that the call to ATC was productive and treated as a learning event by the controllers. Regarding the carbon monoxide; the Reporter's A & P did not find any leaks and because the cabin's fresh air supply pipes from the turbo; not the exhaust manifold; they are convinced the CO warning was false even though it indicated about 150 ppm.



Synopsis: A Columbia 400 pilot had a track deviation after takeoff because he misunderstood his clearance then had a carbon monoxide warning for which he took environmental clearing procedures for while using oxygen; but believes the warning was false.