The 4.3 and auto trans. in my van loses power and vacuum while driving on the hyway after an hour or so. I get vac. back by letting up on the throttle. When it loses power it wont stay at speed without downshifting to thrid gear on flat level road. I've replaced the distributor, cap,rotor, plugs, wires, fuel pump, fuel filter. Don't know what to look at next.
- posted
17 years ago