Volvo V40 Stall when foot off pedal and DSA light on

Has the engine light come on yet?

hi
1: yes it is the gear box
2: I am not sure, but I think yes 1998 gearbox will fit into 2000.
if you have the 1998 gearbox in front of you, then you can compare it

Should be on or near the fuel injector supply rail.

Check fuel line fuel pump

Sounds like the ISC motor is bad.

SCAN CAR SOUND LIKE IDLE SPEED CONTROL PROBLEMS.

you prob have to check your idle control its expensive $185.00 part only.

Have you cleaned the throttle valve and the idle speed control valve, how about the cleaning the fuel injectors? not a can of cleaner but a professional cleaning at the dealer? These three items can all cause your problem and as a pro tech it is where I would start. One more question have you checked the OBD 2 system for trouble codes?

change your fuel filter

If the car shakes and stalls at lights stop signs etc. I would check the egr ( exhaust recirculator valve) first this valve should open when in driving mode and close immediately when engine comes back to idle. to check this find the valve on the intake manifold ( looks like a mushroom) remove vaccuum line and plug hose drive the car and see if it fixes the problem. If it does get one from local parts store. Most brands such as standard are universal and come with baffles that must be installed. do not leave the valve disconnected the engine will "ping" when driving forcing you to buy higher octane gas. It is also illegal to remove this unit for emission reasons.