Hello I’ve been experiencing an issue with my LR 300 MTDI build that I can’t seem to figure out. While tuning the fuel and idle I can’t seem to find a setting in which the motor does not over rev and completely run wild on me. I’ll explain my procedure here.
While trying to tune my fuel in I’ve taken the throttle lever off and backed my fuel screw out quite a ways, then proceeded to work my way up increasing fuel via the fuel screw and increasing idle position. There is a point where the motor will start to stumble and act like it wants to idle. A lot of the time when the motor starts it will go from stumbling to over rev instantly. I’ve also had it set where the motor will start, idle and then slowly rev up until a point where it’ll start to just over rev on its own or when you touch the throttle even slightly from idle it revs out of control. From this point I’ve tried turning my fuel screw down slightly and this will result in either no starts, stumbling, or over rev when it starts with the throttle pulled to give some more fuel. It’s to the point now where I’ve been working on this issue for well over 6 months thinking I’m doing something wrong but I’m starting to wonder if there is another issue at play.. either a bad injector, issue with my pump, or a bad cylinder. The pump was rebuilt a little over a year ago by a professional diesel mechanic so I have a hard time believing the pump is bad. Please help before I pull this motor out and convert this car to a gas job.
Thanks for you help!