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Setting Idle Speed, Balance, C

Setting Idle Speed, Balance, CO & HC on BB512i's

1) Install Hg (Vacum) Gauges, one per side T'ed in to one of several vacum lines to Intake Manifold.

2) Start Engine

3)Sample exhaust gas (before cats, if any) while noticing Hg readings (normal = 15-18in Hg)

4)Balance Vacum slightly side to side, w/air bypass screws (note: balance will fluxuate until all 12 cylnders run correctly)

5) Sample both banks exhaust readings again, before cats, adjust FD screw (idle mixture)until CO is approx. 1.5% on both sides.

6) Recheck & adjust Hg until Both Banks are even (likely about 16 in. Hg)

7) Recheck & Adjust mixture as Necc. to 1.2%-1.5% CO...

if no miss or anomolie exists at this point the HC's should be in the 100-200ppm range (before the cat) with anything over 300 indicative of poor condition of some component, ie: plug, injector, plug wire, cap, FD port, fuel pressure, intake air leak, dirty/sticking/burned valve. .

NOTE: it is not possible to simply set one side then the other. Both sides have to be slowly, methodicaly tweeked to spec, with each insuing round of adjustments calculated to bring both sides to matching Hg/CO/HC readings.

Happy Motoring
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