I have a Y reg 1.7 dti 16 valve (the izuzu engine) astra estate. When i start the car the yellow engine management light comes on, and goes on and off randomlly during the journey. In normal driving the turbo is practically non existant, i can hear it spinning but no boost and terrible engine performance. but the revs stil go to the red, if you can wait that long. Now if i go on the motorway and drive at full throttle in 5th, it will get to about 85mph. I do that for about 10 mins, come off the motorway and the turbos if full form and the engines got load of power, and it stays that way until i turn off the ignition, even if just for a split second.
There are no boost leaks, the turbo isnt seazed, ive changed the oil and filter.
Any other ideas please?
thanks in advance