Hi,
I've been having this somewhat annoying problem of a sticky high idle with
my '69 1600. (By the way, I've really been enjoying both driving this car
and learning about how it works and fixing the occaisional hiccup. Also,
driving the car, what a blast!) These are the details:
When I turn the engine on the car idles fine. When I increase engine
speed and then slowly release the throttle the engine will slow down but
then stick at 2k to 3k rpm. If I snap the throttle (i.e. release it very
quickly) this doesn't happen.
To try and fix this I took apart and cleaned the linkage. This done I
reinstalled the linkage but left the two carbs decoupled (and unhooked
from the throttle cable). The problem still happened with each carb
individually. The throttle shaft would stop it's rotation a few degrees
short of the idle stop and would just sit there. I was able to rotate it
all the way to the idle stop by hand without very much effort
though. With the engine off (but still warm) this problem didn't exist,
the shafts rotate freely.
I suspected that this might be related to a leaking throttle shaft so I
sprayed around the shafts with carb cleaner and observed no dip in the
idle so I don't think that's what's happening. However, there is about .5
mm or less in side to side play of each throttle shaft.
While I had the linkage off of the front carb I thought that I'd try
turning the car on and rotating the throttle shaft by hand (it rotated
very smoothly and freely with the engine off). When I did this it
immediately sucked all the way closed and was very difficult to rotate
open. When it did it popped all the way to full open and was hard to
close. The engine roared, this worried me, so I closed the throttle and
turned off the car. I don't know if this is normal behavior or not.
When I searched the archives it seemed that other people had had these
problems but no one knew what to make of it. So, has anyone figured it
out? Does this sound familiar to anyone? Any suggestions? What do I do?
Sincerely,
Eric Corwin
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