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Discussion Starter #1
Any common causes to look for?

Car runs flawlessly once the idle stabilizes on cold starting. Warm or hot starts are no problem.

Car rarely stalls and and can be caught on the gas pedal most times before it stalls.
 

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Sounds like a temp sensor problem. Both of my cars stumbled on cold start. I changed out the Temp sensor on the red one to fix it.
 

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That is the hidden Bosch coolant temp sensor one hidden betwwen upper and lower hose on thermostat housing not the one next to timing belt cover for gauge.

It should have about 3000-4000 ohms cold and 300-400 hot. Check Bosch 2-wire connector going to it for moisture/corrosion and use dielectric grease on connector. also check for rectangle black rubber seal in connector.

Pull wheel and front inner liner if you need to change it.
 

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Sounds like a temp sensor problem. Both of my cars stumbled on cold start. I changed out the Temp sensor on the red one to fix it.
No CEL though. Can these go bad without throwing a code?

And are these somewhat generic or Alfa specific? Parts are hard to come by up here and I didn't think to salvage any engine sensors when I parted out my scrap car.
 

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No CEL though. Can these go bad without throwing a code?

And are these somewhat generic or Alfa specific? Parts are hard to come by up here and I didn't think to salvage any engine sensors when I parted out my scrap car.
Thanks v much for the feedback.

I also have a 1997 SAAB 9000 with somewhat similar engine management but LH Jetronic rather than Motronic. My SAAB had a air temperature sensor failure but it threw a code.
There is an air temp sensor in air flow meter and I suppose it could be giving your ECU erroneous signal without giving you a code. Did you actually test for codes in memory?

Coolant temp sensors are pretty generic but you should test new one at room temp and see if you get about 3k ohms. I have seen some measure 5k. When i installed a 5k one to test it engine runs pretty smooth and with a cold start faster idle. Maybe fine for a real cold climate like yours but unless is goes down to 300 ohms hot may affect gas mileage. Color code on one 5K I have is black. Original 164 ones usually blue or cream colored but both pretty much the same resistance.

I test them in 164 by just plugging into connector first and start engine and see how it idles and warms up before actually installing it.
 
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