Every time I close the hood on my '05 convertible the check engine light comes on. It clears by itself after driving for a while. Any thoughts on what connector is loose? This also happens occasionally when I wash it.

 

I believe that the hood openings and closings are monitored as part of the adjustment of the service interval.

The first thing I would look at is the switch/sensor in the bonnet hinge. I bet it is bad, particularly if this also happens when the car is washed.

The light clears because it is no longer getting the fault. You might try putting a code reader on after you open and close the hood and before you drive. There may be a fault code. You have to read it before it clears.

Good luck chasing electrical gremlins...

 

I thought codes remain even if the light clears. I know this is the case on my wife's 2001 VW.

 

This is true.

Possibility #1 - There is a wire harness that crosses the radiator shroud right under the rubber seal. Look to see wheather the connector on the T-MAP harness has any rub damage ( it's the sensor on the front of the intake manifold ).