Since owning my s3 the Haldex has been playing up. Making clicking/sucking noises on ignition. Had the car up on the ramp checked the plugs they were corroded. Cleaned it out and the noise went away with the lights on dash. I thought great all fixed. Done some full on launches to test 4x4 no wheel spin just pulled away hard as it should. Then the first rainy day comes the light comes back on... Next day went off when dry...Then pretty much every rainy day it came on again. Now driving the car since it was "fixed" it felt like it was being helded back somehow. Not underpowred but just not right. Now the traction control light is on all the time the car seems much better at pulling away no drag feeling.... Would a Replacement haldex ecu sort this problem? If so where can I buy one that fully works no corrosion checked on eBay there is some but can see them properly. The haldex is due oil and filter change. Will get that done when I know the fault. Any help would be great.
