Hello all, here is my first thread.
I just bought 86 Ram 50 2.0l with Auto Trans. The truck needed alternator and carrier bearing on driveshaft-done. Then oil pressure sensor for light-done. New NGK platinum plugs. Now moving on to getting ready for smog.
So I opened the air cleaner to find the barrel of the Carb with a 12 gauge solid core wire twisted to the bore, preventing the water choke from closing all the way. I took the wire out to see what happens. Choke butterfly closes all the way when cold. Truck starts and dies immediately. If I hold the Accel. pedal down it starts but smokes like crazy. Way too rich. I put the wire back. It starts fine and idles up to operating temp. Progressively, as temp increase choke flap open more and more until wide open. I think it is working fine in respects to opening, just too far closed at cold start.
Once warm the truck seemed to idle too high. I connected a DVOM with RPM function to coil negative and battery. The meter reads 1090 rpm. Spec is 750 +/- 100.
In this picture it displays the MAS (mixture adjust screw). The plug is already removed. I tried adjusting 1/8th turn by turn until I got the highest rpm. I don't know if this is right but I basically just tried to tweak it until rpm peaked.
Now my idle was at 1100. But all the while it was smooth as can be, not missing a beat.
According to a couple other write-ups and alldata the SAS-1 from diagram is the one I turn to adjust idle rpm. Well I tried turning 360 degrees both in and out- nothing.
So I tried to put it back where it was. Next I moved on to SAS-2 and SAS-3 from diagram. I turned both in and then out 360 degrees (seperately) made no difference.
I thought maybe the throttle cable was too tight or the kickdown rod for trans. I checked, they are not the ones holding IDLE high.
Last after looking for awhile I found this screw
It doesn't seem to be located on the diagram, or maybe I don't interpret it right. The screw is located below the choke linkage and behind the choke tamper cover. But sure enough it lowered the idle to 850rpm is where I left it.
The truck is still idling smooth but I am not sure if what I did is correct as far as the other screws or proper adjustment. If any one can offer some suggestions. I believe the truck was originally running too lean, previous plugs were white. I am pretty savvy with cars but carb is just before my time. I am trying to learn though.
Another Question, how does the Oxygen sensor come into play? Alldata said once warm, test voltage output with DMM- should be higher than .8??? mine is .02? Broke or super lean?
Thanks. Sorry if my pics aren't visible, my first detailed attempted write up.