kangaroo kangaroo 1.6 16V zetec 2000

[SteveHayes]

Our lovely 1.6 16V zetec 2000 hatchback (French) is cutting up rough practically all the time.

New points, leads, spark plugs not better.  Then computer said maybe an injector so cleaned the injectors with some additive, a bit better sort of but not what you'd call ok.

Hot or cold.  The way to provoke the stutter is to try to accelerate, just a widgy bit will be enough.  Particularly if the revs are about 2K or less.  We wait at a junction, when we see a gap coming get it up to say 3K revs and gently engage the clutch (which is going to lead to new problems soon enough I fear).  But just driving on a motorway and wanting to speed up a bit will cause a second or two of judders before it picks up.  Changing down using engine braking is smooth.

It reminds me a lot of when the choke was wrong (in the old days).

The independent garage is at a loss (I like them but I don't think they are the greatest diagnosticians, this forum has saved the day in the past when the garage was stumped).

Thanks

[Tdci-Peter]

11 hours ago, SteveHayes said:

The way to provoke the stutter is to try to accelerate, just a widgy bit will be enough.  Particularly if the revs are about 2K or less.

It does seem a bit like a dead spot on the throttle. Could be the position sensor on the throttle body. Or the valve jamming at a certain position.

This can be monitored while driving by a diagnostic system like Forscan, but may show up in the garage, or by resistance checking the sensor after removing it.