Fuck fuck fuck, mother mother fuck, mother mother fuck, mother fuck, mother fuck, noids noids noids!
Well today was a lot of work to be annoyed. So after screwing around with suspension this morning and finding I couldn't do what I needed to do with the parts I had, I pulled the car out with the truck. The goal was get it running awesome! I kept trying to tune the car, and it just wasn't happening. And it seemed to be missing. Didn't seem to be a spark issue, but lopey idle except no cam. Not to mention it's still too rich or too lean. After a bunch of fiddling, I finally called the Datsun guru to get some clarity.
He suggested pulling the injector feeds while running, and/or checking for spark leaks, etc. So even though I just replaced all 6 injectors, I thought, good point, go back to basics. Checked spark, replaced the wires with a spare set I had. No change. Next, started taking off injector plugs. Wouldn't you know it, #2 and #4 had no change when disconnected!! I got annoyed and figured I'd gotten two bad injectors. Swapped connectors, no difference. Batch fire, so they all do the same thing. But after taking a break, I decided to test the injectors. They both clicked when voltage was applied, and I could watch the fuel pressure gauge drop. So I started it back up after confirming spark and listened with a stethoscope. All were clicking accordingly.
Unfortunately it was still missing, I figured I'd better check the compression to confirm no mechanical issue. Compression was 170,166,162,165,166,170, so no issues there. When the plugs were pulled however, #2 looked brand new with no carbon whatsoever, so clearly not firing. Or no fuel at all. #4 was super black, indicating too much fuel.
After many thoughts, the only thing left is an injector pattern test. I have an extra fuel pump, think I'm going to make a little test bench so I can yank the rail off and have it far away from the car then open them full and see what they're spraying like. Either I got two brand new injectors that are crap, or there's a blockage in the fuel rail, though I would be surprised. Something has to be causing an issue though.
Anyway, it's been a maddening day. The only good thing is I have a reason for why I can't tune the car, so I'm not just crappy at it. I may fiddle with it tomorrow or Sunday. I'll let you guys know what I find.
Oh, and the injectors were Intermotor FJ23s, new, not rebuilt.
