The problem:
My 850 has this problem where I need to press on the gas pedal in order for it to start and to idle smoothly. If I don't give it gas when it's a cold startup, it immediately stalls. And after starting it, I have to drive around for a couple of minutes before I can step off the gas without it stalling (e.g. by a stop sign or slowing down for a turn).
When the car has warmed up enough (usually just after a couple of minutes) it runs without stalling but it has a rough idle, like it vibrates a lot. If I turn it off and on again it starts fine, it just has that rough idle.
Here's a video I took (you need sound to hear the differences) -
It's quite annoying, and embarrassingly enough I've had it like this for maybe a year without dealing with it (I've even developed a technique where I use the handbrake so I can keep my foot on the gas while I shift gears when driving out of parkings).
Obviously, I know something is wrong with my car since this never was a problem before it started about a year ago.
What I've done:
I read somewhere about cleaning out the idle air control valve, throttle body and MAF. I think my car doesn't have a MAF but some air temperature sensor instead (a black and blue plug), and I sprayed that with electronic cleaner. I took the IAC out and cleaned it the best I could with some brake cleaner. I didn't take the throttle body out cause I would need a new gasket then, so I just tried to clean it from outside. I also cleaned the flame trap, cause the air hose to the throttle body was really nasty. But nothing changed.
Codes:
A2 111
A3 111
A7 122 - Temp. sensor interval too long
B1 145 - Faulty signal from function selector switch + 418 No control signal to blower fan power stage
B2 122 - Speed has not exceeded 22mph or no speed signal
B5 111
Those are the only codes I got for now. I couldn't get a signal for B6, and I don't think I had anything connected to the rest of the holes.
Anyway I'm assuming the most important one here is the "temp sensor interval too long", and I did notice that the coolant was just above the MIN sign and the temp gauge was a little under 3 O'clock, so a bit lower than normal. But I just noticed that after cleaning the IAC etc... And it felt a bit sluggish when accelerating, though I don't know if that's related.
So, I doubt that the temp could be causing the car to act this way.. Or could it? What I don't understand is why the car won't start without gas when it's cold, but once it's warmed up it's not necessary. And why is the idle so low?
Any ideas on what I can do to narrow down the problem, that doesn't mean spending lots of money on different parts etc?
