cold start idle issue
cold start idle issue
Have an issue with my engine that has been on going since i bought the car. Im a diesel mech. and am stumped, figured id post up and see if anyone has any ideas or experience with this issue. After sitting for a few hours or overnight, i get a rough surging idle for a few seconds at start up. engine runs rough and jumps around and a few seconds later idles just fine. Sometimes have to hold the throttle a bit to get it to smooth out and not die. No fuel/air leaks in the fuel system. I rebuilt the injectors and top end because of a blown head gasket so the issue does not lie there. car runs great other than the small starting issue and it kicks over in a few revolutions. Just the rough idle for a few seconds. Have also noticed it smoke a time or two going down the road. Only thing i can figure is the inj. pump is in need of rebuild, maybe the fuel is running back to the tank. The car is at 270k and has been largely unmolested except for the work i have done. Usually an air leak in the fuel system will cause this but it doesnt exist, ive repaired any possible leaks from the tank on up. Any ideas?
List of things,poss. Burned out glow plug,tight valve, leaky foot valve or valves in inj. pump,low fuel pressure,one or more fuel injectors sticking when cold,this usually caused by dry fuel or over tightened inj.which distorted nozzle barrel,noted by bluing on nozzle pintel. torque is 50 lbs. Injection pump wear.
Good luck