About 2 months ago the yellow warning light for the injection system failure came on, diagnosed by Fiat as "air flow signal fault, so a new air flow meter & air filter was fitted. All fine for 2 months & now it's happened again!!!! Van has been in with Fiat for a few days with no fault diagnosed, but they think it could be a wiring issue. Does anybody have an idea, that maybe i could suggest to the Fiat garage? Many thanks, Ken