I have a 1999 ford expediton 8 cyclinder and my car is putting, not heav but during acceleration. I also smell something funny like not burnt but hot, I can't really describe the smell. I have oil and all my fluids are cool, i even have a full tank of gas. Can someone please help me?

SOURCE: My 1999 Ford Windstar keeps

if it keeps stalling it could be an obstructed fuel filter, a weak fuel pump, or your tps(throttle position sensor) is faulty.

SOURCE: 2005 nissan murano "s" surges and bucks when accelerating.

You need to have your engine flushed and cleaned out. One or more of your spark plugs aint firing. You need to replace them all to include the wires as well. If you dont get your engine flushed, you could blow your engine up.

SOURCE: cant put much gas in tank w/o it coming back out

It souds like the air return line from the fuel filler pipe is plugged. When you fill up the car the air has to escape from the tank or else the fuel backs up into the filler neck shutting off the fuel nozzle. The air pipe is housed in the fuel filler pipe and lets the air escape as the fuel is going into the tank. Remove the filler neck and inspect air bypass line to see if it is kinked or plugged.

SOURCE: Acceleration is jerky (tardy).

After removing ther filter, pour it's contents into a glass jar. dirt/rust will be obvious...Water is heavier than gasoline and will collect at the bottom of the jar and form a visible sepearte "level" or layer. If you find either, the tank needs to be cleaned out. As per your question, this situation dod not happen 'till you serviced it. Therefore it is likely to begin looking at what was just done, before looking at something new. Since synthetic oil has nothing different in it that the engine would respond to, I would not look to that as a problem (unless while working, you accidentally pulled a connector or vacuum hose off.
I too do this for free, I work from what's inside my head, only referring to manuals as a last resort. When I don't know something, I either don't answer or put the issue aside and do a bit of research. There is a "pay side" on FixYa, but anyone relying on that for income is insane...just not enough traffic there. The benefit I get by doing this is to keep my mind working and give assistance to people who otherwise would hav little or no info or help. I enjoy getting a good rating but that is not my primary goal...Getting you running is! I won't comment on that further.
Now let's try to get this puppy fixed!!!

SOURCE: driving home check engine light stated flashing truck lost power

Try checking the map sensor this is a common problem with these vehicles