Hi. I have a 2001 S80 T6. The B6284T engine was swapped by the previous owner to a B6294T, because of transmission failure. (I'm going to refer to them as the 2.8 and the 2.9). It works fine, but neither the ecm or the tcm was exchanged. Before the turbo boost comes, the engine is not really strong, and the turbo lag is insane. I've come to the conclusion that the problem is the camshaft reset valve. On the 2.8 engine only the exhaust side has vvt, but on the 2.9 the intake side has too. Because I have the 2.8 ECM the intake camshaft reset valve is simply not connected. According to Vadis my only option would be to buy a 2.9 ECM maybe even cable harness. Finding a 2.9 ECM is not easy and I would have to swap the throttle body and probably other things too. My questions are:
- I know that the camshaft reset valve is controlled by the load (duty cycle) of a pwm signal. But is there any data about that at given rpm the load should be how much? Is it only a function of rpm? Is it linear? Could I simply use the signal of the exhaust reset valve? If I "played" with the intake reset valve, is there a chance valves hitting the pistons, causing engine failure?
- If I bought an ECM what other modules, drivers sensors should I buy? I already know throttle body on the 2.9 is Bosch and not Magnet-marelli, but what else? The easiest option I know would be a donor car. Can the ECM swap be done with vida dice?

Thank you for your answer 🙂