What causes split BLM?
Thread Starter
Racer
Joined: Feb 2001
Posts: 292
Likes: 0
From: hialeah fl florida
What causes split BLM?
can any one tell me what causes split blm i have a 92 with modifications like a zz9 cam headers no cats ed wright chip. I always have a diff blm for right and left. any fixes to compensate. As far as i know i have no intake or exhaust
leaks have brand new AC delco O2 sensors.
leaks have brand new AC delco O2 sensors.
Melting Slicks
Joined: Apr 2001
Posts: 2,089
Likes: 214
From: Ca.
Re: What causes split BLM? (cesar)
How far off are they? I've noticed a diff. of up to 4 between sides on a lot of cars. GM's tuning is +/_ 4 so that's within "spec.". If it's more than that then I'd be looking again at vac. leaks or leaking/sticking/or plugged inj.
Just ask john25 about vac. leaks...... his 88 only has one side O2 sensor-but with the wide band we picked it up! Lt bank tuned for 128 blms, but then plugged in the wide band on the right side and got F/A ratios of about 19:1.
He just couldn't figure out the runner to plenum gaskets.....sorry John, just had to share that one! :lol:
Just ask john25 about vac. leaks...... his 88 only has one side O2 sensor-but with the wide band we picked it up! Lt bank tuned for 128 blms, but then plugged in the wide band on the right side and got F/A ratios of about 19:1.
He just couldn't figure out the runner to plenum gaskets.....sorry John, just had to share that one! :lol:
Thread Starter
Racer
Joined: Feb 2001
Posts: 292
Likes: 0
From: hialeah fl florida
Re: What causes split BLM? (drive it)
ok they are 1 to 2 numbers away after the y settle 127 to132 124 t0 128 i got close by a experitment i read in a another forum with the scanner i closed the idle screw and the i ac position was around 39 to 40 from like 60 as the iac position was getting to 40 the blm were getting closer together almost equal 126 127 128 127. but if i hit the gas fast they change like 120 and 160 but then they settle again is that normal? car seens to run better idle around 600 going up with the ac in drive drives ok
