My thanks to Ed Sowell, who indicated that “streched” throttle cables are
in fact indicative of bent accelerator pedals. This being the case I have
adjusted the cable in my ’ 89 to respond to the pedal with no delay ( no
slack), all linkages and pulley resting against the stop screws in idling
position. My kickdown switch IS STILL NOT activating either in the driveway
or on the highway at speed. Stomping on the pedal in whatever imaginable
fashion simply does not activate (move forward ) the little sping loaded
“piston” in which the mashined depression should act as a cam engaging the
switch. This piston in the '89 is welded/attached to the end of the
sheating, inside the cylindrical part of the mounting plate. Again, for the
record, the switch is electrically OK, it’s arm is set to a "hair trigger "
clearance closeness to the “cable” ( or rather to the mashined little
piston ). When disassembling and cleaning the mounting plate, I was
surprised to notice how hard it is to compress the spring behind the little
piston - I do not understand how the piston is supposed to overcome the
pressure of such a hard spring. When stomping on the accelerator pedal,
the throttle pulley will hit the stop screw first, having only the
resistance of the throttle plate return springs ( maybe bending a few
things in the process) before the spring loaded piston could get
effectively into motion. It does not move! What am I missing? Recent
treads indicate a number of listers having successfully cleaned/adjusted
this component and getting it to work!
I felt less embarassed to post this prob. after reading Mike Morin’s post
who seemingly has an identical situation, although he is asking for the GM
400 KICKDOWN SPEED. Was’nt this around 65 mi per hr? This is about legal
speed, am I to conclude that the XJS shifts back to 2 nd from 3rd only then
and at a lesser speed, for example in an overtaking situation, when the
accelerator is depressed the engine will have no help from the lower gear
ratio of the 2 nd gear?
Any help from those who have been there is greatly appreciated.
Lee Opausky, 89 XJS coupe, 88Kkm, GM 400, apparently operated for 8 years
with no kickdown…
My thanks to Ed Sowell, who indicated that “streched”
throttle cables are
in fact indicative of bent accelerator pedals. This being the
case I have
adjusted the cable in my ’ 89 to respond to the pedal with no
delay ( no
slack), all linkages and pulley resting against the stop
screws in idling
position. My kickdown switch IS STILL NOT activating either
in the driveway
or on the highway at speed. Stomping on the pedal in whatever
imaginable
Have you eliminated the stuff after the switch as a possible source
of problems.
Try driving it around with the kick down switch taped closed. If
It never changes you’ve got a cable problem, else you’ve got an
electrical or trans problem. If it clicks (with the ignition key
on), you’ve got a trans problem.
The solenoid in my trans would click, but the screen inside it
was blocked. A rinse in kerosene fixed that. Also gave an
opportunity for a well needed fluid and filter change.