p0235 & p0089 error codes - any suggestions?

Hi there,
Having some issues at the moment. Symptoms include infrequent engine stuttering (maybe every hour, if driving for 2-3 hours) when driving main roads at 100-120kph. Engine light comes on. Also experiencing random cut-outs when at low speeds. I turn the ignition off and on again and then continue to drive as normal.

Getting two error codes coming up on on the OBD, p0235 & p0089.

Drives as normal otherwise.

I found this link but wondering if anyone else has experienced similar symptoms/issues and tracked down the cause?

http://p0235.enginetroublecode.com/fiat-ducato

Thanks all,
Tom, from a misty and windy Keel beach.

I would say that the answer is in the link you have provided.