I have a question about power loss at 4000rpm to 4500rpm - its like a sudden electrical stutter or fuel loss, I have changed the plugs, leads and coil pack 2 days ago, so I know this is not the issue, any ideas as I know the ST170 has many 'known' faults.
In addition to this, every morning without fail, I start the car, it starts then you can feel a judder (again like an electrical break down or fuel loss) then it stops, you can turn it over a few times and no start, then all of a sudden it starts and is fine from then on?! when I finish work I dont have this issue, it starts first time?!
My first thought is fuel pump for the problem at 4000 to 4500 rpm as if the pump cannot keep up with the engine speed and again with the morning start.
Any help would be appreciated before I start replacing parts