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Just an interested observer on this thread, but dang George, you are amazing. I love your approach to diagnosing and I learn something from so many of your posts! Thanks!!
Just an interested observer on this thread, but dang George, you are amazing. I love your approach to diagnosing and I learn something from so many of your posts! Thanks!!
Thank you Christine, I am glad to be part of the team
Alright, once more as requested.
1. Cam retard is dead on 0 after doing a little adjusting and re-checking once bolted down.
2. Pulled the crank sensor and cleaned it up, absolutely no damage on it or the wheel teeth, I thought about touching the timing chain with something while the hole was open but I completely forgot to do so before re-installing
3. I performed drop cylinder both at the distributor and plug wires, results below
Minimum idle with all cylinders plugged in: 700RPM
Minimum idle with cylinder 3 unplugged: 680RPM
Minimum idle with cylinder 5 unplugged: 640RPM
4. I haven't pulled them since the distributor install on Wednesday but I can do so soon and send over some pictures
5. Fuel trims provided before are ranges, minimum~maximum, should have clarified before
7. Got some measurements at ambient
ECT: 68F
IAT: 69F
MAP: 29.8Hg
All 02 Sensors were bouncing between 430 ~ 450 mV
LTFT1%: 12
LTFT2%: -1
8. I know you didn't request it, but I know that a vacuum test can tell a lot about valve health, so I attached a gauge to the booster line from the manifold, video attached, tested at idle and 2400 - 2600 RPM.
1) Did your misfire stay as cylinder 3 after cam retard set to 0?
3) This does suggest that cylinder 3 is contributing less power although the results are not dramatic
5) Your fuel trims are interesting. Always add st and LT trims on a given bank. Using averages for your ranges, none of the readings are way out of bounds and bank 2 is totally normal. Bank 1 however goes from +5 at idles to -5 at 2500 rpm. That suggests unmetered air on that bank (cylinder 3). Have you done the LIM gaskets yet? Have you checked for exhaust leaks, especially on bank 1?
7) How do those sensor readings compare to ambient at your location that day? Precat O2 sensors should vary between approx 0.15v and 0.85v, switching about one per second at idle. The post cat sensor should be steady between 04v and 0.7v. Your previous graph suggests this but your current description does not. Can you clarify? What is the history on the 2 precat sensors?
8) What conclusion do you draw from your vacuum gauge test?
