need thoughts on 456 troubles

My money is on the wires, esp if they are the originals.
John Cribb told me they are an eventual trouble spot.
They have a COP solution available on their website.
I’d look at the wires first.

 

Had a similar problem a few weeks ago. I thought the plugs very beyond reproach, as they are only 15K miles old (replaced 9 years ago by the previous owner!) but decided to changed them anyway. They were COOKED - DONE - KAPUT! I couldn't believe the engine was actually still running on those things. I swapped the old Champion plugs with new Denso Iridiums and now she purrs like a kitten. No more misfire codes.

My take: start with the easiest potential solution first.

 

Can't believe your car was still using the Champions. Those things went out years ago, along with points and distributors .

I liked, and had always used Denso Iridiums in my boosted cars, but they didn't seem to idle as smoothly in the Ferrari as the NGK's, so I reverted back to the NGK's. Just MHO.

To the OP, yes, check your plugs first before investing in a new set of wires or a new COP system.

 

John- I am running the NGK iridium plugs, too. The NGK plugs that came out of her a couple of years ago still looked good.

 

Forget the seat potentiometer. The price will cause you to want to hang yourself. Nevermind the labor to install the thing, which is also horrendous if the seat has to come out.

There is a workaround that may work for you, depending on your problem. Sometimes, my seat motors would decide they didn't want to move the seats forward and back. I would say once out of 50 tries, the seat would say, "screw you." I discovered a clever trick. If I got out of the car, lifted the lever at the rear of the backrest and moved the backrest forward as if I were entering the rear seat, and then attempted to move the seat forward and back using the forward/back seat movement button while the seat backrest was positioned forward, this maneuver would reset the seat. The seat would then operate normally while driving until the next random "screw you."

 

This helped me after my father of all people tilted the seat and used the seat switch to move it forward with the switch, the seat wouldn't go backwards after the seat back locked in. I tiled the seat and moved it all the way back.. bingo all good.

 

Have a picture?

 

Not sure about 456's, but a regular seat runner is two inverted channel sections with a couple of rollers taking the weight, and held by ball bearings trapped in opposed concave sections on the sides of the U channel. Might be worth folding your body into a pretzel and having a peek under there (I doubt it's in a parts diagram)