Transit Lean Running Injector Issue

A lean running condition on your Transit can stem from several issues. Have you considered checking the mass air flow (MAF) sensor? A faulty MAF can provide incorrect data to the engine control unit (ECU), causing it to miscalculate the air-fuel ratio. Also, when was the last time you inspected or replaced the spark plugs and the throttle body? Problems with the spark plugs can affect proper combustion, which may lead to rough running.

MAF and plugs seem fine. Throttle body looks clean too. Could a dodgy injector cause these lean running symptoms?

A defective fuel injector could very well be the culprit. A malfunctioning injector could fail to deliver the necessary fuel volume, resulting in a lean condition. Given the symptoms you have described, I would advise you to have a workshop examine the injectors individually to ascertain if they are working within proper parameters. Please consider that an incorrect air-fuel ratio for an extended time may cause further damage.

Thanks, it was indeed the injectors. Replaced them, cost 515€, and it's running smoothly again.