ive got a 55plate vauxhall vivaro with the f9q760 engine, my problem is that my rev counter is bobbing up and down. it tends to do it at low speeds ie 20mph ish? and when stationary its gose down to zero then flicks up and down but wile this is happening the glow plug light is flashing on and off like a disco? has any one come across this before ?? now it wont start at all,,, i want to find out as much as i can before i take it any were to be looked at many thanks

Edited by Avant on 19/03/2016 at 11:18