Hi, A few weeks ago we had the "Go to dealer - engine management failure" light come on as we were overtaking.
Took it into the AlfaShop in Norwich who plugged in the computer and said it was showing a turbo pressure fault. They took it out for a quick run and said it felt fine.
A few weeks later the light came on again.
Most of our driving is in the city at 30-40mph, changing up before 3000rpm and using the torque. Both times when the light has come on we were accelerating and going over 3000rpm. Each time the car was started with the warning light on it would accelerate to over 3000rpm once, but would then refuse to rev over 3000 until the ignition was turned off and the engine started again.
Reading these forums I discovered our car has a variable vane turbo ( I had no idea
) and that these sometimes fail, and I found a topic that even had a quick movie of how the vanes work.
So, at low engine speeds (99% of our driving) the vanes make the turbo produce maximum boost, but as the revs increase the boost is lowered. So thinking through what was happening, I thought the vane actuator on ours must have been faulty and was staying closed, giving too high a boost pressure at higher revs and causing the ecu to give the warning and limiting the engine speed.
Now I had to find out where the vane actuator was, and again I found it with help from searching this forum
I eventually found a split in a rubber vacuum pipe coming out of the actuator control solenoid fitted to the top of the radiator I replaced this with a length of motorcycle fuel pipe I had laying around in the garage.
I took it out for a run and although the warning light was still on it revved over 3000 several times and pulled really well.
I had it booked in at the AlfaShop again to turn off the light and told them what I had replaced and the symptoms. Paul(?) the mechanic noticed my replacement tube had collapsed when the engine was running so he replaced it with a thicker walled tube and turned off the warning light.
I would like to give a big thanks to Phillip, Paul and all at the AlfaShop for turning off the warning light twice and fitting a new vacuum pipe and sending me on my way completely free of charge. I can't recommend these guys highly enough.
So far no warning light and I have been driving it a bit more like an Alfa should be driven.