i have been experiencing what i call a dead throttle pedal. when i start from a stop the car starts to accelerate and then after about 1 second it's as if you turned the key off. no matter how far you push the throttle, nothing happens. if you let off the pedal then push it again it usually responds, but sometimes you have to do this several times. it is not consistent, there is no pattern to this behavior. it has been doing this for over a year and i have taken it in at least 8 times for this problem. the dealer says, there are no error codes and they cannot replicate this when they test drive it. they even had a tech take it home and still they says it does not do it.

 

Assuming your Q7 has turbo, it sounds me like like the ultimate turbo lag is happening (like no turbo at all and the engine is starving for air). But the fact that the dealer has drove it several times and doesn't observe any issues is beyond me. The symptoms of what you are describing would be unmistakable...

 

i do not have a turbo. i have driven cars with big time turbo lag such as the first audi TT. these symptoms are not like turbo lag. i think it could be the throttle position sensor that fails Intermittently then works properly so there is no error code. without an error code the dealer will do nothing. thanks for the your reply.