Hi there. My ford focus over the past few months seems to chug and stutter when driving at 30mph. To stop it chugging you either need to drop a gear or speed up for it to go. Ive had it hooked up to a diagnostic computer but nothing is showing up. Also when you stop accelerating and the car meant to be smooth its as though the engine in my car moves or something. Any ideas what could be wrong. Im going to take it to another garage. Someone i know did mention about the throttle sensor but ive no clue. Thanks in advance.

3 hours ago, lyndsey said:

Also when you stop accelerating and the car meant to be smooth its as though the engine in my car moves or something

So with the throttle pedal fully released, it feels like the car is pulling a bit sometimes? Instead of just gently slowing down.

Try driving in 2nd gear on a flat, empty road without touching the throttle. The car should pull smoothly along, at idle speed (850rpm normally). Then very gently ease the throttle open, to get up to say 2000 rpm. See if there is any power dips or jumps. Release throttle completely, let it slow down naturally, and see if it stabilises smoothly back to idle speed.

It just could be the throttle pedal sensor, very small errors in the signals from this will cause unsteady power, especially at small throttle openings. Large errors will be detected & light an error lamp/message. But there are quite a few other possibilities, so the more you can test it and describe clear, repeatable symptoms, the better.

Any clanking or banging on engine start & stop? That might indicate a DMF problem, but I hope not!

Though sometimes with minor faults, you have to let them develop to the point where a light comes on, with a code, or they have identifiable symptoms. Changing bits on spec. is very expensive!

Oh, and which tdci is it? Might help someone to recognise a problem.

Peter.