The problem is solved! Former owner has installed a cheap, poor quality air filter! Now the car is okay !! thank you for all your great suggestions and tips !! great forum, with great people!
Excuse my bad English .. I should probably worked harder at school ... unfortunately I have been having problems with my 1999 Suburban 6.5 .. bought it a week ago. it ran terrific !! but a few days ago, I drove heavy loads. suddenly all power away .. was like running into a marsh ... began to...