Unreliable starting under certain weather conditions

I have owned a 2001 996 since 2018. It had 46k on it when I bought it and have added 20k since. Have had a problem that no one has offered any thoughts on: occasionally in cold or cool temps and / or damp conditions, the engine will not turn over. The only consistent "message" or sign I've noticed when this occurs is the digital time and the oil (?) level display, lower right side of the dash, does not exhibit the oil level (?). The digital oil level display beside the time is like a "swoop" and counts down in seconds. When the count down starts and shows 5 seconds, the car cranks right up. Sometimes when the count down shows a higher number than 5 (like 54) the car will start. If that doesn't show, it ain't gonna start!! Because the key switch action had been soft for quite awhile, I recently had the switch replaced ($2k+/-). Seemed to solve the problem until the last few days (cool and damp). Anyone have a similar experience? None of the service outlets, dealer or independent, can explain. Thanks!

Age of battery? Do you have a solid 12V at the terminal in the engine bay? Have you ever had the Y-cable replaced from the terminal to the starter/alternator? What does the voltmeter say on the dash running/not running? Places to start...

Don't forget the ground cables also, Battery need a complete path.

Please clarify.... When it acts up the starter does not spin...no sound, no nothing. Or strater spins but engine does not fire? Sorry to be so basic but u have ti be very specific with the conditon for us to lead u down the correct path

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^^^^^^ and when this happens, do you just walk away ? for a day, week, month , year? ...then return to find it functions as normal again? Or do you try a few things to attempt to get a good result? and what are these things you try?

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Thanks. I replaced the battery in March 2021 and when the key is turned on all the lights on the dash come on. The amps on the digital gauge read just a hair under 12 when the car isn't running. As I recall (the car won't start today; its cool and rainy) when the engine is running he amps read 12-14.

Starter does not spin; no sound, nothing.

I jiggle the key; turn it off and on again, and again, and again.... Open the door, remove the key, pump the clutch, nothing changes. in the past I have cussed a good bit and walked away for a period, maybe later the same day maybe the next. Lately I have continued to turn the key off and then back on until I get the digital read for the oil and then it starts. This usually loses my interest after about 5 minutes.

You paid $2k to replace the ignition switch ???? Wow . Your symptoms sure seem like a ignition switch issue . Start with basics: have the battery load tested . Inspect the battery ground cable for corrosion . Check OBD for any stored codes . Good luck

The meter on the left is measuring volts, not amps. If you don't have a volt meter, you should buy one and measure the voltage, with the engine off, at the jump start point to the right of the power steering. + side there and - side is the bolt holding the airbox in place. See what you get there and report back.

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Exactly what part of the ignition switch was replaced, and with what (Porsche OE, or some other brand)? Sure sounds like the electrical part of the ignition switch.

Is it a convertable or stored outside, if so your drains may ne clogged? The imobilizer under the drivers seat is known to get real flacky if it gets wet. Put your hand under the seat and see if the carpet is damp.

So I over-remembered the cost. It was actually just under $1,200; still a lot in my mind and wallet. I will have the battery load tested and check the ground cable OBD. Stopped raining overnight and it started this afternoon. Not feeling any moisture under the driver's seat.

Yes it is a convertible and stored outside. When stored for more than a week I use a cover. checked under the seat today and its dry. Rain stopped last night and it started.

So a no spin from a starter can be several things. I dont think its the battery as it sounds like the car starts normally most of the time. 1. Not getting the start signal to the starter because of the immobilzer under the seat or a bad connection to the relay. I would check for power/ground to the relay from the computer, its on the relay tray behind the back seat. Next the relay needs to be tested. 2. If that all checks out u need to verify voltage to the starter and amperage draw when u command the starter. If low or none at starter then its a heavy guage wire issue. Usually corrosion on the "y" cable or motor ground. Its on the passenger side under the muffler. 3. If there is power to the starter and a good ground....the starter is bad. The diagnostics need to be done or u r just tossing money at a problem and hoping for the best.