MainePorsche

Guys,
Within the last week I find I have no kickdown function. It was working great.
I have engagement of the bracket with the peddle switch. I have transmission solenoid click when peddle switch activated with foot with ignition on. Transmission is one of Greg Brown's 'new' ones I installed. It has 1500 miles on it. Still looks brand new

From Search, Wally says:

'Quiet place, ignition on, flip the parallel kickdown switch - there should be a click from the solenoid on the transmission.

If there is no click, check for 12 vdc on the throttle switch - there should be power on one side. If so, press the switch (ignition on) - there should now be power on both switch terminals.

If you have power on both sides of the switch, move to the solenoid and check for 12 vdc on the solenoid wire with ignition on and throttle switch depressed. Repeat with the parallel switch.

If you have power at the solenoid, but no click, solenoid is faulty or sticking.'

I'm not clear as to what throttle switch Wally is referring to check.
Also, what results/testing conditions would one undertake at the CE panel to determine if the relay is faulted ?

I'd like to get the kickdown back.

Thanks in Advance.
Craig
__________________

jpitman2

I think Wally's switch is the one under the gas pedal. If you get the click at the rear with WOT, the relay is OK. AFAIK the box wont kickdown unless you have at least SOME throttle in, above that required to maintain current speed. Is it possible the throttle cable to the box has slackened off?
jp 83 Euro S AT 55k

MainePorsche

Thanks jp.
Come to think of it, I noted the loss of kickdown just after having the L valve cover off and quad detached. When I reassembled I checked at the quad, and my throttle switch clicks on the slightest movement of the throttle cable. I will inspect further down under for slackening however.

Mrmerlin

always a good thing to ask what was the last thing I fixed ,

and to add this info into the original post as it makes diagnosis easier.

Maybe the throttle cable is too tight, it should have a small amount of play before you hear the click from closed throttle to opening.

Wally is asking about the kickdown switch thats under the gas pedal inside the car,
make sure that the pedal and the switch are both touching when the pedal is pushed down hard.
NOTE test kickdown with the engine off and the key in the run position.

mdkelly1

Other than "no kick-down" under throttle acceleration, does the car shift normally as you gradually depress the accelerator when starting off.

In other words, does it hold the gears (second-to-third, third-to-fourth) longer proportionately as you depress the accelerator further? If so, that will eliminate one possible cause of "no kick-down."

If not, then check to be sure the cable end at the transmission is still attached to the actuating arm.

MainePorsche

Stan, David thanks.
It sounds like it will not be an electrical issue so far.
Car otherwise shifts like a gem.
After coffee and important paper work done, I'll get to both cables.

dr bob

The kickdown cable is the one (of four) that use a removable wire retainer to secure the cable end to the ball on the bellcrank. If that was not restored on reassembly of the quadrant, there's a chance the TV cable is no longer connected. Of course, you'd probably notice the soggy performance from early upshifts too.

SMTCapeCod

O.K, I can dive into my new Ebay acquisition, publication WKD 490 620, A28 Troubleshooting Guide.

Which, by the way, also indicates 1st gear start for all 85/86 cars.

And technically, it doesn't cover S4 and up...

But:
Code "F5", Complaint: No kickdown downshifts.

Possible Damage Causes, see Reference: PR6 PR9, IN5, IN6, IN6.6

PR6: Control pressure cable maladjusted or not connected.
PR9: Electrical fault. Check k-d switch, valve must be heard when it opens AND closes w/ignition on.

IN5: Kickdown solenoid valve. Remove valve and check function (ground wire required), inspect o-ring precisely.[sic]
IN6: Fault in valve body. Disassemble, clean or replace.
IN6.6: Check movement of valve no. 40 in valve body.

MainePorsche

Thank you so much.
I'm thinking the control pressure cable (Bowden) needs adjusting.
Will report back.

MainePorsche

After I installed a 'new' GB transmission I had set the throttle cable tension at the quad so the slightest movement gave me the click of the throttle switch. I also set the control pressure control cable tension to just slightly slackened for the timing of the shifts to accommodate the traffic I drive in the town up here - 25 mph - it still would kickdown but the aggressiveness of shifting minimized for the turtle like local traffic patterns. Must have tugged on something when I recently detached the quad. Inspected everything re the throttle and 'kickdown' cable - all good.
The fix was by slightly (I mean slightly) decreasing the tension on the throttle cable and increasing the tension on the 'kickdown' cable. Test drove several times to fine tune, and shifting is still butter like and kickdown is back.
Thanks all.
Craig

SMTCapeCod

Pretty crazy the sensitivity. Especially given that the cables much stretch over the vehicle's lifespan and other tolerances change.

Glad it was so simple! Also helpful to me to hear that the hair-trigger TPS settting didn't need to be backed up, I had that chalked in as a suspect for causing some lassitude w/my car.

MainePorsche

Yes, the sensitivity in the 'kickdown' cable adjustment is impressive. Several trials on the same road, with similar accelerations, and one could feel the difference in the fine tuning until satisfied. Good to have the kickdown back.
Actually did give the throttle cable/switch activation a hair of an adjustment too.

MainePorsche

Also slightly de-tensioned the pedal cable to insure complete throwdown of the peddle to be sure arm activates the kickdown button. Cruise cable re-checked for to maintain its slight laxity too.