Hey everyone, I just picked up a 2000 s40 an I am having some issues with it. When I got it, it ran like a champ but itwould not start right away an after some research I found it to be a fuel pressure regulator. So now after changing it out it starts right up but it seems to stumble when I accelerate a little hard. I can't even leave a light very fast. If I am sittin at a light an the car is in drive i can feel it stumble while its idleing, but if I put it into nuetral it idles like a dream. It seems like it has air in the fuel line but it has been awhile since I changed out the regulator so I would think that any air would have been pushed out. Any help would be greatly appreciated. Thanks

 

Check engine light on?
Maybe it is misfiring.