engine fault light comes on intermittently, was diagnosed as glow plug controller. This has been renewed and all the plugs are of similar electrical resistance. engine starts and run O.K.
if you have a heater plug at fault then your light would be on permanently,I would have a look at your EGR valve which are bad for sticking on these and sometimes free themselves off hence intermittent management light problems and also the turbo waste gate for seizure but a code reader should pinpoint your problem
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