[dannmarr]

Harvey,
The symptom is like a hesitation, choking feel with some stuttering. This happens only going up hill at around 40-50 mph with the pedal pushed hard. For example, I'm driving up hill at around 50. Suddenly the car in front of me slows down and we both slow down to 40 mph. Now he speeds up and I follow pushing the pedal down to pick up momentum, this is when I feel this symptom. To stop it, I either let go of the pedal and start again but slowly picking up speed or I switch to 3rd.
I changed the spark plugs, one bad coil, added the power mode and the quick change kit from you. It ran better, so it seemed until I found the iris vacuum check valve off the hose.