Rowley010 wrote:Yes I do believe it's a ford engine in there.
It seems to be that no matter where I let the revs drop to from between 1st and 2nd I get a jerk. I don't believe there is any clutch issues my car (I have a good mechanic I trust and get it serviced regularly).
The only time I don't get a jerk between those 2 low gears is if I literally only Rev it in 1st to around 1400rpm and then let it drop to 1000 before letting the clutch up, which is clearly no goof when wanting some good firm acceleration without holding up traffic behind, or when want to pull away on a hill!
From your descriptions, that is the typical behaviour of the TDCi engine.
Firstly, there is an aggressive anti-stall below 1,250 rpm, unless the clutch pedal switch detected your clutch is out. When you change gear, you may have inadvertently trigger the anti-stall some of the time but not the other depending on your clutch pedal position, throttle position and engine revs combination.
Secondly, you clutch pedal switch may be faulty (or intermittently faulty) as mine was in my car (fixed under warranty).
Thirdly, you are on turbo might be on boost or still building boost pressure in first as your change into second, which will be off-boost), making the transition even more difficult to control.
I have two workarounds without taken a very, very relaxed change or double-declutch
1) I did what you said to change out of 1st before the turbo comes on boost at below 1,600 rpm and catch the throttle in time so it does not activate the anti-stall as you lift the clutch in second.
2) I would stay in 1st for longer to 2,500 rpm and do a sustained throttle change so I stay on the turbo when I lift the clutch in second at over 1,700 rpm.
I felt the anti-stall activation is based on the engine revs and the clutch position sensor rather than the throttle. As a result, the actual throttle behaviour will not feel correlated to the throttle pedal position, hence sometimes you can more and sometimes less than you think you need on the throttle. This inconsistency will result in the jerkiness your described as you try to predict what the engine management system may do, rather than reacting to what the ECU has already done.
Hope this make sense.