wierd volvo((( I'm dissapointed, really... fuel problems

Pablo check to see how th accesory drive looks being that it drives the pump everytime i change fuel pump on d12d accesory is usually done and they need to be replaced as a pair if accesory worn out bad it wont drive properly also. Check and maybe replace the fuel filter housing they have a lot of problems feom that #### as far as the drain back valve are u talking about the valve on the intake manifold. Ive never heard of a head being cracked on the fuel passage or seen it for that matter also possible is bad injector. Let me know what it turns out to be please cuz i deal with d12d on a daily basis and would like to know. Also very possible is a bent valve ive had that before with black smoke. But the engine when running ran like #### no effect on fuel psi. Is the any kind of mixing going on as far as fuel and oil or coolant

 

some inj. are bad out of box, can you press, ck. for leak/down of fuel, had 2 bad out of 6, right out of box did same thing.

 

check and see if the egr valves are stuck open

 

The heads are very tuff I would think more like injectors or cups are u doing this at home

 

I would look very carefully at injectors /cups/rockers/ engine brake pistons in the rockers

 

When u check the pistons in the rockers make sure the back of the piston has not come unscrewed it should be flat

 

Did u properly adjust injectors possible cup not sitting right or damaged