Limp mode

My SC 1KZTE has developed  a fault keeps slipping into limp mode usually after coasting (its automatic) down hill for a while and when you accelerate up hill it will not increase revs and engine light comes on stop the engine and start again its back to normal. Am thinking its the fueling valve on injector pump thats not working correctly the question is is it the valve thats faulty or is it the dreaded ecu capacitors that control the valve, had a look at the said capacitors last year and they looked like new . Anyone cured the same problem help is much appreciated.

Are you coasting in neutral? If so, try leaving it in drive as it could be the autobox ECU complaining (coasting in neutral is frowned upon for auto boxes as the oil pump is driven at the input side).

Also have you had your engine ECU updates with new capacitors?

never coast in neutral just meant going down hill with no throttle have not replaced capacitors just looked at them, did 250 miles today slipped into limp mode once and am fairly positive its air in the system just a bit mystified because its so sporadic. Had to pull over on the A1 restarted and it cleared did another 60 miles no problem.

The word on the street was that even if the capacitors looked fine they were not, they drag down the regulated 5V and interrupt the job the the ECU.

So as you a) have an intermittent fault and b) the old capacitors I'd say that was the primary suspicion.
If you do replace them and you still get the problem it's something else: but you still end up with a better ECU

So it's a win or win-win to change the caps in my view.