I have tried to get my garage to fix engine fault. But the the fault is intermittent. Back to dealer they checked with their code reader and think it’s engine airflow sensor. Tried Toyota main dealer and was fobbed off they said their equipment wouldn’t be able to recognise the fault code as it was an import. So back to garage to get fault rechecked. Most likely I’ll be replacing 3 sensors. ££££££ ouch. 

hi David this airflow sensor is a common problem not just on alphards  and there are vids on you yube on how to clean them with a common spirit so try that first.Dave

Can of electric contact cleaner for £3.

I cleaned mine the other day and found a dead fly sitting on the sensor. Probably a job to add to the annual service schedule tbh. New MAF sensors can be had for about £40 and take 10 mins to fit, tops.

Back to local garage after trying to get Toyota main dealer help. Apparently their fault code machine don’t understand Toyota imports! Stupid I know. Hey ho my go to garage replaced air management sensor. So far it has cured problem. Engine seems to run smooth and long motorway journey was good. Uphill at 70 MPH. Fingers crossed no ££££££.