The AC/heater (HVAC) system may unexpectedly switch to the defrost mode when accelerating. This system is operated by engine vacuum and should be inspected for any vacuum leaks if this problem develops.  There is also a revised vacuum check valve available to address this concern.

On 3.9L V6 and 5.9L V8 engines, the intake manifold gasket may leak and cause increased oil consumption and a spark knock during acceleration; the gasket should be replaced.

Leak detection pump failure can be caused by the internal diaphragm switch sticking, or in some cases, contamination from debris or carbon particles from vapor canister. If black carbon particles are present in the LDP, replace vapor canister in addition to LDP. The purge solenoid should also be checked for debris or carbon contamination and replaced as necessary. All evap system hoses are subject to cracking and splitting causing leaks, Inspe...

The van is running very very sluggish, it drives at about 20 mph. The engine sounds good, not knocking or other noises.

power booster is new,ascalipers and master cylinder

At 85,000 miles a frayed cable window regulator was removed and window was lifted and help in place with a piece of wood.Cable was pushed out of way when window was used.And replaced 2 weeks later...