My 2000XK8 stumbles now and then when starting out. No restricted message. When I give it more accelerator it goes good. All this is @ normal operating temp. Any idea what could cause this.

 

Likely a vacuum leak.

 

I had a customer's 1999 XK8 back when it was in Jaguar factory warranty that did the same thing on occasion. I drove the car home with me several times and finally felt the 'stumble' from takeoff, standing start.

I forget how I diagnosed the fault (WDS datalogger???) but I did swap out the MAFS with another car and it cured the fault.

I ordered a new MAFS for the car and returned it to the customer (case closed).

You might monitor the MAFS with a generic scanner and watch the readings when it happens (better to have 2 people, 1 to drive and the other to watch).

Like "The Coupe" said it could also just be an intake manifold leak.

bob gauff