I'm having intermittent problems when changing from 3rd to 4th gear only. When at 2,500 revs, the revs will fly upto approx 4,000 and drop down quickly to 2,500...Whilst driving at a faster speed and changing gears from 3 to 4...I'm obviously in higher revs yet it happens so quickly, the car shudders!! Has anyone got any thoughts on this??

I think ur problem is dirty injectors & so carried on driving, planning to have it checked at the next service.