My 1996 Subaru Legacy Outback is not accelorating well & feels like it is slipping.

Is this a manual transmission you are talking about or an auto?

it is an automatic. I hade the code read...it was 01125. Said something about it having to do with the coolant system. Right now I do not have a thermostat in my car, and I live in Maine where it COLD. So, I am thinking that this has happened becasuse the engine is not able to heat up properly...? I am going to put a thermostat in it tomorrow. Do you think that what I have said would cause the car to do the sputtering and feeling of going to stall out when it is in low speed and at a stop? I will get back to you after I out in the thermostat and let you kow if that fixes it! Thanks

well I would be interested to know if that made a difference or not, I can't think of a reason why it would though. One of my cars has a thermostat that is stuck open and it runs fine in even -25* weather, I just don't get any heat from the vents and the coolant temp guage dosn't budge when it hits 10* or less. If the thermostat fixes it then great if not give me some more info on what the engine is doing exactally such as any sounds it's making, any funny vibrations, roughley what RPM range it is happening in. Also while the trans fluid was the proper color (red I am assuming) did you notice a metalic spakle to it?

Tranny fluid is good. No noises. Just a jerking sputter, and then at a complete stop for a few minutes it keeps doing that, and then starts to feel like it is going to stall out. It only happens when car is going slow or stopped. Once I get the speed past 50 it does not do it at all. My temp gauge is at normal temp when wramied up, and at a stop, but when driving it goes below the C. I am putting in thermostat tomorrow. I will get back to you!