Hyundai Repair: 98 hyundai elantra trouble, hyundai elantra, battery connections


Question
its seems as tho whenever the weather turns cold my car starts having problems. since the weather has been cold, or cooler, whenever i stop (such as at a light or stop sign) my car will just shut off, so i have to put it back in park, turn the key off, and then back on. it did this last year too when it was cold. now today it did something new, not only did it die at a stop sign, but it died when i was slowing down to go around a curve. also whenever i touch the brake, there is a clicking sound and the check engine light will come on for a few seconds.....
....another problem i've also been havin is shifting. its an automatic but when it shifts gears it shifts so hard....please help me. thanks

Answer
Start by checking your battery and alternator.  Make sure the battery connections are tight, that the battery is securely held in place, and that nothing metal (such as the battery hold-down) can contact the positive battery terminal.  

Also check your transmission fluid level and condition for the transmission issue.  

If those are okay, you should next have the diagnostic trouble codes from both the ECM and TCM read.  Any codes present may provide significant assistance to finding the root of the issue.