My car was out of commission for awhile due to the rack and pinion needing to be replaced. We fixed that, but now there is something else wrong. It is really sluggish to go. If you are on a flat road you can get the speed up; however if you even think of a hill you lose speed down to like 35 mph. It stutters when you are in any gear but park if you aren't giving it gas.It also dies a lot if you try to idle in drive w/o giving it steady gas. It will also die if you turn the wheel completely to the left. The gears change fine on a flat road, but once you hit a hill the rpms are going you can feel the car struggling and sometimes the rpms shoot up in to almost danger area with no change in speed. It sucks down about a 1/2 tank of gas in one day just driving in town.The check engine light is flashing. Went to auto zone so they could do a diagnostic. Came back as a coolant temp problem they said I probably just need a new engine coolant temp sensor, so got it and changed it, it didn't help. I have put two fuel injector cleaners in it, checked all the fluids, gave it transmission fluid, etc. Does anybody have any idea what might be wrong?