Thermotime Switch shenanigans?

[ck848]

In trying to diagnose something completely unrelated (FV and FV relay...)...

I was looking in my engine bay and noticed the previous owner or mechanic had disconnected the red wire to the thermotime switch (and heat shrunk the connector).

Now I'm wondering what the heck is going on. It's been getting colder in the PNW recently. With temperatures dropping into the low 40's overnight. I garage the car but its frigid in there. Over the last few weeks I've been struggling with starts more - the car sputters and pops in the 500rpm range for a little bit and then catches fully then runs like normal.

Questions for the brain trust: Is there any reason to break the thermotime circuit? It seems really not a great idea to not have the cold start injectors firing on a cold start.

As a note: I've already reconnected the circuit and ironically the car struggled more to start - took 2-3 cranks to come alive (but did not sputter). Drove it around the block for a few minutes - came back and cycled the car - fired right back up (but I suspect because the engine is already warmer - I'll retest in the morning).

[PeteKz]

SWAG: The PO may have disconnected the TTS because it wasn't working correctly, and a new TTS is over $300. it should be connected if the TTS is working.

There are several threads here about the TTS and the Bently 911 SC manual and the CIS primer discuss how the TTS works and how to test it.

Do you have the manual and a CIS pressure gauge kit?

[ck848]

I just ordered the Bentley last night so eagerly awaiting it to show up and start reading up more on it.

I don't have a CIS pressure gauge kit - but I'll put it on my list of things to buy.

I'll search the forums some more and test the TTS. Thx Pete!

[PeteKz]

Here's the FI test kit I have. It's cheap Chinazon stuff, but good enough for occasional DIY use. It comes with enough adaptors to test any fuel injection system.

https://www.amazon.com/BETOOLL-Injection-Pressure-Tester-Gauge/dp/B01L17TPT2/ref=sr_1_6?crid=354BVGIUTF6VX&dib=eyJ2IjoiMSJ9.FLBBSWalWw5V7o9dbf2woPMxehNTNVAnx YF8pEobKr190LoXGw7syd1D3Mb-yLOhs2Qhm_XX4BBFPf0KcaXLwqIaMBMnJABQwERtUrf0bKmFAA-NO5SqcnYvCKIREz6vsaQUyKBYEDcz3uSvV2h48Xe3M0OTqYHvn 3i7lNoqUactTiTe9L1S3XAsBnJJs9YCty32lzXl6ACwpWJBroc ngyAXu6XSxHCqOLV_n6ornAwm_lD6L4eZTCUVK13qq50-Jz2RnqzNvXvxpjI2i-EhG4oobuY8c3yeKb5g8DsX5xM.cIfsNsRRxIXxXssB-FSyDiRUFqOxu47ywFGW8DPgLkg&dib_tag=se&keywords=fuel%2Binjection%2Btester%2Bkit&qid=1731657152&sprefix=fuel%2Binjection%2Btester%2Caps%2C458&sr=8-6&th=1