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!
BF2, this could be your problem.
While trying to tune my fuel in I’ve taken the throttle lever off
Did you mark the position of the lever PRIOR to removing it? My guess is that you need to mark it now and then take it off again. But when you go to install it back on turn the lever backwards, not the hub in the injection pump just the position of the lever, and set it on ONE spline counterclockwise to what you had.
This will push the throttle mechanism inside the pump all the way back to where it needs to be at idle. Now try to start it and set the idle where you want it. You may need to adjust some of the fuel out of the equation first to get the RPMs down.
Just what I would do if I had that problem. Hope it gets you a solution.
Thanks for the reply. The throttle bracket I have has 5 marks on it that line up with the slot on the throttle shaft as a reference for tuning. I’ve tried it on the lowest settings (as far counterclockwise as possible) that usually results in no start and stumbling when I throttle up about half way through the range. I wish I had a picture for reference.
Sounds alot like what I went through with my MTDI pump.
Where did you get it?
What are the pump numbers?
I had to get another pump.
I got the pump off the internet somewhere. It’s been about 3 years so I can’t remember exactly where. It’s funny before the rebuild the motor started, idled, and reved fine. It just wouldn’t pull fuel because it was all gummed up. Now i can’t get it to run remotely as well as it did the first time I started it. For some reason the website isn’t cooperating with my phone to post pictures of the numbers on the pump, but it’s on my build thread. Here’s the link:
http://vwdiesel.net/forum/index.php/topic,37865.msg361036.html#msg361036