Strange rattle noise
 

I have a strange rattle sound that I can hear from inside my 87 911 which comes from behind the seats in right side of the car when the windows are closed. It starts at 2200 rpm and I can hear it up to about 3000 rpm. It seems to only be present while driving the car. I do not hear it when the windows are open and I hear it even when it is in neutral while the car is moving. If I'm parked and rev the motor it does not make the sound. My first thought was chain tensioners, but I'm not sure. I just had the valves adjusted and a full service done on the car. My mechanic is the one who pointed out the noise when I picked it up, but we have not determined what it is. Any thoughts?

Thanks

I have an 87 carrera and i think i have the same noise, more like a popping or tapping noise than a rattle, comes from right rear close to rear fender inlet, have removed rear seats and still have noise, will let you know if or when i find it

I know the tapping thing is a part in the right rear fender which does on occasion tap the fender in my car as well. I put a little foam rubber piece in between it and the fender right beside the hood hinge and that went away. My sound is definitely on the mechanical side and it sounds like its coming from the front of the motor to the right a little, just behind the seats.