Limp Mode

[dellabella]

Hello

i'm a newbie today. Have already posted on another forum but i think i mistakenly posted onto an american site! Like i said...a newbie!

Here's my problem.

I drive a Rav D4D (diesel). Driving is fine up to 60 mph. As soon as I drive over 60, the speed drops right down into limp mode, about 30 mph. The only way to get out of this is to pull over, let the engine idle for about 30 seconds and drive. Or if possible, depress the clutch and freewheel for about 30 seconds and then engage the clutch again and get the speed up. This could happen once per journey or 2,3,4,5 times. No hard and fast rule, it just happens sporadically. Took the car to a Main Toyota dealer 2 days ago. They ran the diagnostics on it and found nothing. No fault was apparent. Am tearing my hair out. Any ideas please?

Many thanks

dellabella