my a4 1.8t has a bad sputtering problem. it runs really rough and sometimes won't even accelerate. ive already changed the mass air flow sensor and the throttle body. it threw a code that said (left bank 1 too lean). i think that was from the vacuum leak. ive already fixed the vacuum leak and its still running like crap. someone please help!

 

Is the check engine light on? What exactly is it doing (or not doing)?

 

yea the check engine light is on but i havent turned it off after i fixed the vacuum leak. it idles really rough and when i try to accelerate it will start sputting and wont accelerate.most the time when i gas it and it hits about 4,000 rpm it starts shaking and the rpm doesnt move. kinda like a misfire

 

is the CEL flashing? This definitely sounds like a bad coil, very common problem. Check codes to be sure.

 

cel? your talking about a coil pack right. do those throw a code? because ive heard they do and dont

 

cel is check engine light. when they are completely out they throw a flashing code. some people talk about them gradually going out and not giving a code, but ive never had that.

 

yes my cel is on but it says (system too lean bank 1) im pertty sure that was from the vacuum leak. and i fixed that.

 

you could have more than one code stored.

 

yea ill get that looked at in the morning and ill get back at u. i guess if theres no more codes ill buy a coil pack. and swith it out one at a time to c if that fixes it. let me know if u got any more suggestions though.I appreciate it

 

yo i had it checked out this morning and it came back with a new code. (knock sensor) i know the motor isit knocking. i think its from it running so rough. but i cleared the codes ive been driving it all day and the cel hasnt came back on. u still think it could be the coil.