idle speed again

[Soma576@xxxx]

Hello all,

if you can remember, a couple days ago i posted about my idle switch not 
kicking down every time i let my foot off of the gas. i worked on the 
problem today and here is what i have found:

i adjusted the spring on the throttle one more notch. it's pretty tight now 
(i think mine was already adjusted forward). i also adjusted the throttle 
linkage. right now it is all set up so that if i have the pedal to the 
floor, the throttle hits the full throttle switch, and when i let the pedal 
all the way back down, it is pushing on the idle speed switch w/o any 
additional play on the switch. when i have a screwdriver pushed down on the 
idle speed switch, my idle screw is adjusted so that i am running at about 
800 rpm or so. STILL, when i put my foot on the gas and let the pedal back 
down, the idle doesn't kick down!!! it sits at about 1200 RPM. however if 
the car is at say a stop sign, i can hit the gas with my foot on the clutch 
and let it drop down fast, and THEN it will kick down. i can't find any 
mechanical reason why is should be like this. i would think the switch 
doesn't care if it is tripped hard or softly - it is still being tripped.

my questions:

1. how far into the idle speed switch is too much? should the screw be 
pushing on the switch all of the way, medium, or just enough to take the tab 
off the switch?

2. basically every adjustment you make throws something else off. how do i 
set up the linkage so that when the pedal is fully depressed i know that the 
throttle butterflies are wide open? theoretically my car could be adjusted 
so all the switches hit correctly however my butterflies are not adjusted 
correctly. i don't know how you could measure this w/o removing the intake 
W-pipe. is there another way? perhaps something with a perfect throttle 
could measure how long their linkage is in millimeters and could turn mine so 
that it matches, and then set up my screws to go along with that? this is 
complicated!

3. the shop manual says that the idle ECU recieves a ground when the 
butterflies are fully closed. if my butterflies are off, perhaps my ECU 
isn't recieving a ground all of the time unless i let the gas off quickly, 
maybe hitting the butterflies hard and making it all work? just a theory. 
how do i test it?

4. how do i know if my idle speed motor is working? under which conditions 
should which things happen. i'm not proficient with a DVOM so if anyone has 
any ideas, they will have to tell me how to hook everything up.

is there something else i'm missing? i'm inclined to believe my butterflies 
are part of the problem. i really need someone to guide me through complete 
adjustment of the throttle system.

if anyone out there has any better ideas on the problem, please let me know!

Andy

Soma576@xxxx
1982 DeLorean DMC-12 VIN#11596
Fargo, ND 58102


[Non-text portions of this message have been removed]