International Lancia Forums

Having been told that the turbo by pass valve should be replaced every 24,000 miles and knowing that mine had not been changed for the last five years( lots of miles) I decided to replace it. The main improvement has been at low speed pick up which is more down to the fact that the vacume pipe from the manifold first go's to the fuel pressure regulator and then to the turbo by pass valve.The by pass valve when removed was faulty in such that when sucking on the vacume side, air was being drawn though from the turbo pipe section of the valve body.I also can detect less turbo lag and a high pitch whisle on full foot to the floor acceleration has stopped. Also when reving the engine i can now hear a whoose of air through the valve( bonnet open head inside engine) when releasing the thottle.

Has anybody got more storys to tell on i changed this ??? and this happened?

Further to my last comments on the turbo by pass valve the high pitch whisle is caused by the waste gate opening. Because my by pass valve was not opening the waste gate was opening sooner then normal. Now only when I am giving it some really heavy acceleration does this happen.