A few weeks ago, my car began having some strange problems. I would try to accelerate but it would not move as usual, occasionally hanging up and bouncing back and forth as if I was tapping the accelerator pad with my foot and the check engine light came on. I took it in and they told me I had a bad O2 sensor and it was replaced, all was well...

Recently, this has been happening again, however when I took it in, they found no problems with it. The engine light doesn't come on and it only happens randomly. At a few points, when idled, the car would drop the RPMs to 0 and the engine would shut off and I would have to start the car again. It did it again just yesterday and it shut off on me, however it only happened once. It revs up fine without having the car in gear but when I try to dry, it seems like it's hesitating to move and then just jumps into movement and then lags out again. Does anyone have any idea as to what this could be? I'm no car mechanic so any details would really help if I have to reset the ECU or whatnot. Thanks in advance for your help, this is really bothering me!

 

Your situation can be as simple as doing the "MAP whack" and ECU reset to something far more complicated (Idle Air Control, Throttle Position sensor). It's interesting that your tech indicated an O2 code was thrown. This may have only been part of the problem and it could have also been coincidental with some other related issue. O2 sensor, MAP, IAC, TPS are all involved with fuel metering. Try the first suggestions I gave and see what happens. It's something you can do fairly quickly at home and could save you another trip to the dealer.

ps. I'm going to edit your title to reflect something more descriptive. There's just too many threads in the archives asking for "HELP". And of course, most of what's posted in here are "weird car problems".

pps. Since you indicated in your post in the other thread that you don't know how to do this procedure, here they are:
http://forums.s2ki.com/forums/index.php?showtopic=209708
Follow the steps for clearing the CEL:
http://forums.s2ki.com/forums/index.php?showtopic=183490

ppps. If you look at the top of the "Technical" section in UTH, you'll see a stickied thread, "FAQ's". There, you will find all kinds of "How To's".

 

Ok, thanks for the reply. I tried doing the "map whack" and will test it out once I get out of work. I'm about to go outside now and reset the ECU, hopefully this fixes my problems. Thanks for the title change as well.