When I start the car it is sluggish starting and wants to stall, I can gas it and rev the engine and it goes fine. As soon as I let off the gas to put it in drive it starts choking and sputtering and stalls. We took it to the shop last week and had the spark plugs replaced (had been a while since a tune up, if ever). Now it's same exact problem again. I've heard fuel filter, fuel pump, throttle plate needs cleaned, something about an engine control module. So, any ideas anyone? I know nothing. I was set on fuel filter but saw something that said it would go with that and just act like it wanted to stall but not actually stall. I have no clue. Please help. 76,000 miles. No idea of engine size, v6 maybe, nothing fancy just the reg. 4 door sedan. Sorry to sound so dumb.