OK, I am having a real brain buster with my car. I have an AUDI A4 2003 1.8. I am new to owning an Audi's and new to forum

OK, i bought this car in early sept. About 2.5 weeks ago. I started having an problem. My fans would kick on when my car was shut off and would drain my battery. took the car to the shop. Was told it need a temp sensor and a temp control Module. Had them Installed. Problem still kept happening. I called the garage. Guy said to bring it back in he had an idea of what it could be. Told me till then just disconnect the neg batter cable when i shut the car off. I did this and had not issues till last night.

while driving the car. my epc light and check engine light came on. I could not accelerate. hit the gas and nothing. All instruments stayed on. I believe so did the engine, till i stopped then it shut off. tryed to start it up and it just sputtered. then it would start and shut off when i got it into gear. i finally got it running again. but spend a good 10-15 min. with trying to get the car to turn over, or would it would start and stop. after the first time the check engine light came on. it didn't come on again. i think the epc light came on once. when the car started its seemed like it was running ok. but didnt have as much power as it usual does.

this morning i tried starting it and same deal. wouldnt turn over the epc light came on once. then it would turn over then shut off. Then, turn over stay on a bit longer then shut off.

does anyone have any idea what it would be? Do the first and the second issue go hand in hand with any problem? Im a little lost .