Hi,
I've got an escort (R reg) 1.8 zetec (115ps version) that runs a bit rough. At idle (when warm) the revs aren't stable, randomly go between 800 and
1000, the engine vibrates when running rough and smooth when ok. When driving at a constant speed it feels like the power is fluctuating in the same way, but when you accelerate it seems fine, pulls fine, no misfire or anything right to the red line.
So far I've changed the air filter, plugs (which were badly needing changed), plug leads, ignition coil pack and crank pos sensor. All common problems I've been told with this model. But they've not made much difference with the problem.
There are no obvious leaks. Throttle position sensor and MAF sensor are next suspects. Any better guesses out there?
David