Thanks for all your replies.

I'm certain that the lockup is causing this condition. The trans slips fine and the howling is only evident under light throttle load at full lockup.

If you accelerate from 0-60, this is never experienced.

When this condition is met, it feels like the car is driving over a cattle grid, its even slows it down marginally, requiring added throttle to avoid speed decay.

I *really* hope the radiator and the trans doesnt need changing, as thats just catastrophic. I'll drive the car in the river Dart if thats the only answer.

If the TCU needs changing, can anyone give any pointers on where it is? Also, if any UK members know of anyone who sells the part. I'm very aware than an updated firmware was released for the 722.6, does anyone know what I should be asking for?

Thanks again for your replies and time.

Kind regards,

Mike Freeman