U.S market import.
Fuel gauge in gallons,speedometer in miles,different style steering wheel and airbag,ecc in F,passenger side airbag in '95 (E.U market cars didn't had them untill '96)and no side blinkers on the fenders.

... But, after have waited 15 mn idling, the coolant gauge, to the top, came to the bottom and get again to the top. Ect or it's wiring are bad. Ect being bad...the engine ecu doesn't know what is the engine temperature and don't know how much fuel to inject and engine can stall,cut out or will not...

When engine is idling...ect sends signal to ecu and then ecu sends signal to iac valve for idle speed. Iac valve is active only when engine is at idle & gas pedal at rest...as soon as you press the gas pedal iac valve is closed and throttle plate takes the induction of air to the engine. TPS sen...

ECT sensor or it's wiring.

Check from both....sensor side and engine wiring loom side.

Engine temp gauge and cooling fan behavior are classic symptoms of bad ECT(or it's wiring).

Remove it and toss it in the bin!
You are chasing your tail with this crap.

Oe Volvo or at least Vernet.

all right Guys. I will order one to Volvo. Thanks. If your old ECT was original and was working properly...you might re-install it and see how the engine runs. Chances are that you don't even need a new one. Don't forget to remove negative battery cable while installing the old one...in order to re...

P80 ideal offset is a factory one which is ET 43. On 850 you can go with ET 49 and 7J as long as you don't go wider than 205(205/50 or 55 16). I have factory alloy wheels from gen.I S80 as a winter set on my 850. 215 can't fit because of a strut clearance on front. Not sure about s,v70. However...6 ...

When you know that ignition components,engine and a turbo on turbo engine are in good shape...real lack of power is almost always a bad vacuum lines from turbo.

Always check simple things first!

Port A6?

https://www.matthewsvolvosite.com/read-codes-volvo-850/

A1 1-1-4 should be sorted out.
It's program selector open or short circuit to supply.

I just saw that your car is '94 850 GLE.
GLE in EU is 10v car...should be in AUS too.
Is it 2.0 or 2.5?

Is it 10v or 20v?
Ignition cables are not interchangeable between these two engines.

About transmission codes...it could be PNP switch or S,E & W switch on center console.