Sounds like dirty/misadjusted score motor switches.

Weak outhole kick pulse can be any of these:

Dirty/misadjusted switches on the outhole and ball index relays.

Dirty/misadjusted score motor switch.

Hi pbm3
I think You should buy manual and schema --- then showing snippets of schema of "interesting areas" . ipdb has nothing to Toledo / Valencia.

I agree with You (post-5): Every given ball starts with "one Bonus for free" - a feature I do not like, makes the pin more complicated.
I believe Your pin has an "Bonus-Relay" - when You loose a ball - ball rolls into Outhole - Bonus-Relay is activated - lets the Bonus-Unit step down - Bonus-Relay DROPS OUT , Outhole-Relay pulls-in, steps the Bonus-Ladder up one step, kicks the ball over to the Shooter-Alley.

So I would have a close look at the Bonus-Unit - last step stepping to ZERO - I believe ONE Switch OPENS and at the same time: A Make-and-Brake-Switch is moved.
The Bonus-Relay must pull-in so Bonus-Ladder is stepped down - but in the end it MUST DROP-OUT.

I can show it on Wms Little Chief, my JPG, red Numbers:
Ball rolls into Outhole, closes red-1, IMPORTANT: red-2 is active (there ARE Bonus on the Ladder. Red-3 pulls-in, establishes Self-HOld-Current (red-4) --- after a long time Bonus-Counter gets to Zero, so red-5 will open.
In the meantime theough red-6, 7, 8, 9: Bonus-Ladder is stepped down. Reaching Position-Zero: red-5 opens, (therefore red-11 closes again) - Switch red-2-red-10 moves to red-10, red-12 gets active --- then red-13 and red-14 and red-15 (Bonus step-up), also red-13 and red-16 and red-17.

Maybe You are lucky and find a "switch to open" and an "Make and Brake Switch to move" - the two switches that are moved when the Bpnus-Ladder is steppd from Pos-1 to Pos-Zero.
Anyway - I advice (my belief: EVERY pin should have manual and schema): Buy the paper-stuff. Greetings Rolf

aLittle-chief-Work3b_(resized).jpg

Hi. I dont have that pin, but if you look at the schematic, you will find the switches involved in reset.
they will be going from the score reel coil, to the reset relays. the reset relays need to be checked for switch gapping.
also, I think, the start relay may be part of it too.
and a switch on the score motor will pulse the reels 5 times per 1/3 rotation of score motor...I think thats right.
it sounds like a switch is gapped too close, and a good rattle, makes them short together??? just guessing.
does it reset at the same place each time?

Hi pbm3
if Your pin would be a "Satin Doll" - I would say: "a Normally-Open Switch on Reset-Relay" is faulty ALWAYS closed.

I show two snippets of ipdb-schema "Satin Doll". WE MUST KEEP IN MIND: Whenever a (playfield) feature calls for "Help of Score-Motor doing a turn (Williams, Bally: 180 degrees)": EVERY SWITCH ON EVERY WHEEL ON SCORE-MOTOR WILL BE ACTUATED.
The feature calling for help (of Score-Motor turn) does CLOSE one or more switches ALSO in the circuitry TO LET PASS THE SHOTS OF ELECTRICITY THE SCORE-MOTOR-SWITCH(ES) LET PASS. Other relays "not wanting help of Score-Motor: They have their switches OPEN.

Look at the snippet of schema --- lets say the ball hits a target "worth 50 points" - (marked orange) the 50-points-relay pulls-in, lets the Score-Motor run.
You already have made some single points - SCORE-DRUM-Switches (marked orange) are NO LONGER at Zero --- The Switch (marked red) on Reset-Relay is faulty always closed: The Score-Reset-Relay is pulsed (marked orange) by the turning Score-Motor ((((actually) the Score-Motor turns for to help on Scoring-50-points))).

And so (marked green): The pulsing Score-Reset-Relay does "Reset the Score-Reels" ...

pbm3, can You show these interesting parts of YOUR schema ?
Question: Does Your pin always "faulty reset" WHEN a playfield-feature makes the Score-Motor turn ? (((like: making 50 points or 500 points or 5000 points or alike))) Greetings Rolf

Satin-Doll-Work-for-Toledo-pinside_(resized).jpg