Engine Stalling

[t_marat]

My car had been idle for the past two days. Temps were about -35C to -40C during night and about -30C during day. Currently its about -20C.

I started the engine (after several trials). It seems to work fine at idle. But if while on the move, press the pedal trying to accelerate, it does nothing. the rev does not go up, it stalls. I have to press the pedal really carefully, slowly, only after that it accelerates.
At first I thought maybe the fuel is frozen in the tank. The tank was less than one third, maybe about 15-20 litres. But then when I am in the first gear I am able to rev up to 5000rpm, albeit slowly, and it holds it without problems. I read in past somebody's post saying if the fuel pump is not working to full power, the engine would stall at high revs.

I added another 20litres into the tank, it didn't help.

When I slowly rev up the engine, it goes up no problems.

What is the problem? Something with electronics? Logically for me it seems like something related with fuel delivery.

[genphreak]

My car had been idle for the past two days. Temps were about -35C to -40C during night and about -30C during day. Currently its about -20C.
I started the engine (after several trials). It seems to work fine at idle. But if while on the move, press the pedal trying to accelerate, it does nothing. the rev does not go up, it stalls. I have to press the pedal really carefully, slowly, only after that it accelerates.

It is likley the AFM air vane (flap) is jamming inside the aluminum AFM housing.

If you undo the large hose clamp and pull the intake boot (air filter side) use a good torch to inspect the edges around the flap for scratches. It might just be the cold shrinking the AFM housing (I had one in Australia that was warped due to the 40+ heat once). Easy to fix, repalce the AFM or take it off and file the edges of the flap so it moves freely again. Could be fuel too, but most likely the cold is getting to the aged intake components...

[t_marat]

What is AFM? You mean the flaps (vane) in front of the radiator?
The fan shroud is plastic.

[t_marat]

OK. AFM is an air flow meter. Will I need to open the box which houses the air filter?

[t_marat]

The other thing is that I warmed up the engine till operating temperature (middle of the temp gauge). So the engine bay is warm, not that cold.

[genphreak]

OK. AFM is an air flow meter. Will I need to open the box which houses the air filter?

no. Best to remove the boot and look for scrape marks. Push the flap in and out with your finger and listen/feel for scraping. If you can verify it is, remove the AFM (unlplug the connector, undo the 3x 12mm nuts underneath) remove the intake hoses and lift it off the valve cover so you can get it inside where and work on it in comfort.

Make sure there is no rubbish inside when you put it back on the car as anything left inside it will go into your engine... Nick

[genphreak]

The other thing is that I warmed up the engine till operating temperature (middle of the temp gauge). So the engine bay is warm, not that cold.

Check if I am right by removing the intake boot first and seeing if the flap is scraping first. Also, make sure you DO NOT DAMAGE the air temperature sensor inside it (it sticks up in front of the air flap) if you start messing with it, or you will be buying a new one, which you might need to do anyway if this fix does not work out.

[t_marat]

Well, came home. Then went back to work and the engine now works fine. The power was lost only once, about 10 secs, but then everything normalised.