Misfire BLM data
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Misfire BLM data
Well, I went back and took some data again. Figured with all the stuff I've attempted in the last several months, it'd be good to remap the BLMs.
Here's what I found.
Driver's side - 132
Passenger side - 125
Then I started removing injector plugs....
Removed #1 - BLM = 160
Removed #3 - BLM = 160
Removed #5 - BLM = 154
Removed #7 - BLM = 160
Removed #2 - BLM = 139
Removed #4 - BLM = 157
Removed #6 - BLM = 160
Removed #8 - BLM = 150
Then, I started with the spark plug wires... (didn't do every single one, but...)
Removed #1 - BLM = 138
Removed #3 - BLM = 140
Removed #2 - BLM = 136
Removed #8 - BLM = 142
BLM's didn't shoot up on this test as with the injector plug test...
Thoughts?
Here's what I found.
Driver's side - 132
Passenger side - 125
Then I started removing injector plugs....
Removed #1 - BLM = 160
Removed #3 - BLM = 160
Removed #5 - BLM = 154
Removed #7 - BLM = 160
Removed #2 - BLM = 139
Removed #4 - BLM = 157
Removed #6 - BLM = 160
Removed #8 - BLM = 150
Then, I started with the spark plug wires... (didn't do every single one, but...)
Removed #1 - BLM = 138
Removed #3 - BLM = 140
Removed #2 - BLM = 136
Removed #8 - BLM = 142
BLM's didn't shoot up on this test as with the injector plug test...
Thoughts?
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Joined: Jan 2002
Posts: 1,162
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From: California
Car: Z28
Engine: L98
Transmission: T56
not quite sure what we were testing for here?
I would guess the reason the BLM went up higher when you pulled injector wires is because you were shooting huge slugs of air down the exhaust.
when you pulled the plug wire, you were sending ~ 10% fuel down the pipe (displaces some oxygen), PLUS the fuel probably burned at least some of the oxygen in your header primary.
from a different angle: your cylinder #8, and especially #2, don't seem to be contributing much air to your exhaust.
Makes one wonder if there is some validity to (as an engine health test), pull one injector wire at a time, and measure just how much raw oxygen is dumped into the exhaust by each cylinder?
It certainly would look like your cylinder #2 isn't able to pump as much raw oxygen as the rest. then again - i don't know where your o2 sensor was mounted, or what type of manifolds/headers you're using, so maybe there is a distribution issue too (whereever the o2 sensor is mounted, it doesn't "see" as much of #2's exhaust as the rest of the engine).
hmmm
I would guess the reason the BLM went up higher when you pulled injector wires is because you were shooting huge slugs of air down the exhaust.
when you pulled the plug wire, you were sending ~ 10% fuel down the pipe (displaces some oxygen), PLUS the fuel probably burned at least some of the oxygen in your header primary.
from a different angle: your cylinder #8, and especially #2, don't seem to be contributing much air to your exhaust.
Makes one wonder if there is some validity to (as an engine health test), pull one injector wire at a time, and measure just how much raw oxygen is dumped into the exhaust by each cylinder?
It certainly would look like your cylinder #2 isn't able to pump as much raw oxygen as the rest. then again - i don't know where your o2 sensor was mounted, or what type of manifolds/headers you're using, so maybe there is a distribution issue too (whereever the o2 sensor is mounted, it doesn't "see" as much of #2's exhaust as the rest of the engine).
hmmm
Joined: Mar 2000
Posts: 1,692
Likes: 1
From: Corona
Car: 92 Form, 91 Z28, 89 GTA, 86 Z28
Engine: BP383 vortech, BP383, 5.7 TPI, LG4
Transmission: 4L60e, 700R4, 700R4..
Axle/Gears: 3.27, 2.73
Number 8 may be just as good as the others and is masked by the #4 exhaust pulse that occurs just after it (and vice versa, and same on 5, and not sure why 7 didn't, but who cares).
#2 still looks 90% dead. Does the injector click? That plug wire shoots out a spark, right?
The O2 sensor has a little bit of catalytic reaction going on, and the air fuel could be burning in the exhaust a little still - ignited by other exhaust, etc, which could exlain the plug wire results.
#2 still looks 90% dead. Does the injector click? That plug wire shoots out a spark, right?
The O2 sensor has a little bit of catalytic reaction going on, and the air fuel could be burning in the exhaust a little still - ignited by other exhaust, etc, which could exlain the plug wire results.
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