CIS experts-click here

[JShadzi at aol.com]

<< More thoughts on this.>>

Good, good...
 
<< 1. before we go any further, the CISE3 ignition is independetn of the
 fuel system.>>

Ya, you are right, there is a seperate ignition unit, but what about water 
temp sensor, that is shared by both, I guess some splicing of harnesses would 
be needed?
 
<<2. I think you should ditch the fuel ECU - too many dumb things to hook
 up to try to fake it into simple runnign the ISV.>>

Yes, that would be great... I will hopefully be finishing development of a 
distributorless ignition system soon, maybe this fall, so it will be mute 
anyway.
 
 <<3a.  If you could build a solid state "thing" that takes the coil signal
 as an input and generates a square wave (we'd have to measure a running
 ISV to determine the rough frequency to use) with a variable pulse width
 that is inversely proportional to the coil frequency, this would run the
 ISV all on its own.  baselines... about a 30% duty cycle for the signal
 for a warm engine and 4000 pulses/second.  Cold engine the ISV runs up
 to about 70% duty cycle, your device might be quick enough to grab the
 "stumbling" cold engine and give it air to that rate while it warms up. 
 This device would be turned on by the idle switch.  To duplicat the way
 the old ECU ran the ISV you would give the ISV a constant 12v and use
 the "device" pulse train to ground the ISV "intermittently.">>

Yup, totally right, my ECU actually has this capability, I was just hoping 
the ISV would plug in and work, oh well
 
 <<3b.  bag the ISV.  You already have cold enrichment from your EFI,
 andyou can tweak that til its perfect I'm sure.  The other thing you
 need to run a cold engine is more air - i would suggest using a good old
 Auxiliary Air Valve from a CIS system to bypass the throttle body (same
 place as the ISV).  These have an internal heater running on constant
 12v, and slowly close as they warm up.   Your idle would not be "rock
 solid" with a device like this, and emissions would be affected slightly
 due to any fuel/air imbalances while warming up, but it would work.>>

Yup, its a lilttle rough when cold, needs a little throttle to keep it at 
idle speed, but after about a minute it sets into an 1100 rpm idle, then to 
about 850 once warm.  I like your idea about the idle air bypass, as long as 
it holds up to serious boost, but ur-q came with them.  I think I will try 
this and see if it help the cold start idle, really the only issue right now.
 
 <<4.  I don't remember if the CISE3 ign. control also tweaks the idle by
 playing with the timing a little bit or not...  >>

I know it affects timing dependent on temp., not sure if it does so to 
control idle, somehow, from time spent setting the timing, at idle the timing 
is pretty solid, so I doubt it.

<<Hope this helps!>>

Yes, thanks!
Javad