1HZ Injector Pump Timing Mystery

Jun 6, 2011
I've had my 1HZ HZJ77 for about a year and I've done quite a bit of maintenance on it. When I first got the rig I was getting some black smoke under load and the idle was pretty rattily. I decided to pull the injector and bench test them, sure enough their spray patterns were terrible. I picked up some new Denso nozzles, installed them, and checked their crack pressure. Everything was dead on spec so I installed them with some new glow plugs and fired it up. It ran a lot better, but I was surprised to see some black smoke under WOT. Definitely worse when cold. Next step, and probably the wrong step, was to pull some fuel from from the pump. That seemed to help a little but I was still getting black smoke and idle was still rattily. I raised the idle set point to counter some of the vibrations in idle which seemed to help. Anyway, today I checked timing and it came out to around 1.5 mm! I was surprised it was that high. I lowered it to 1.06 mm and now I'm blowing white smoke. Damnit. So it appears I'm running too retarded. I don't get it. Any ideas?

Edit: White smoke was just air in the system. She runs beautiful now. So smooth.

No idea wtf someone advanced the timing that much.
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