I have a 2004 Elantra that has recently been giving us some trouble. It went into "limp-home" mode at which time my friend reset the car to get it running which I assume erased the codes because when I had the codes checked, nothing came up. I waited for about a month with no troubles and then it started having the same problems with kicking into the safe mode. I took it straight down to the auto parts store and NO codes came up. At first I believed it to be the input or output speed sensor but now that I have no codes to tell me for sure I am stumped. I obviously don't want to buy new sensors ($$) and have it be a completely different issue. Here is what is happening...
Car tries to shift into higher gear and there is a big "clunk" then it goes into safe mode and the dash lights all flash or tick. The radio loses all power as well. I can drive it home but as soon as I let it idle it will die. If I happen to get it home and turn the engine off then it won't restart without jumping the battery.
Without codes am I going to be able to pinpoint the issue? Should I take it to someone with a better code reader, or is that not the issue?
Thanks for your help!