I have a 97 suburban with a 6.5 turbo diesel. Recently it has been hard starting, rough idle, surging while driving, and lots of black smoke on acceleration. I changed the fuel filter, checked for air restrictions, and inspected the turbo. No air restrictions and turbo was fine. I then checked boost and had none, checked vacum and had NO vacum. Changed the vacum pump(It was bad) and now it starts good, idles good, and no more surging. However while driving if you constantly acellerate it still black smokes out the exhaust, Not near as bad as before, but still to much. It has good power, and once you reach your desired speed and back off the acelerator it does not smoke. Only while slowly and constantly acelerating does it black smoke. Could this be a overfueling problem? I thought black smoke was an air problem and blueish gray smoke was fuel. HELP
No garages round here seem to know what the problem is, Any help would be greatly appreciated. Billy
Linear Mode
