OK, I've tampered and the book says it is Factory adj. Mr Haynes is not helpful hear.
Question; what is the correct method to adjust the 'idle adj in the plenum chamber'. Currently I have the Allen Screw 5 turns out. I assume it is a compromise to work with the 'Air Bypass Valve' RR is a 1990 with theLucas Hot Wire System. Thankyou in advance, John
On or around Mon, 5 Mar 2007 22:43:15 +1300, "Milcom Instrumentation" enlightened us thusly:
you need to set the base idle. disconnect or block the fat pipe that goes from the intake to the stepper motor valve at the back of the plenum; you can do this by pinching it with a mole or similar.
Set the base idle, IIRC about 500 rpm.
when you release the pipe it should speed up and stabilise at about 750 or so.
Load the engine (on an auto, put it in D, on a manual, put it in gear and come up gently on the clutch 'til the revs drop, or turn on all the lights and blower and wipers), the revs should dip and then stabilise at about 750 again, unload it and they should go up a bit and then stabilise once more.
If it doesn't do this, the stepper is probably not working correctly. sometimes, it can be cleaned to good effect, if not it has to be replaced, assuming the connections to it are sound, of course.
665 to 735 RPM
Dont forget to have the engine hot before you adjust the idle speed.
Alex
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