The cat converter on my 1999 2.2L Sonoma went to pieces internally: lots of rattling, like broken stuff rolling around in a can. At the same time, a steady "Service Engine Soon" light came on. I got a new OBDII cat installed this a.m. The Service Engine light is still on and I'm wondering how long it will take the ECM to figure out the problem is fixed and turn the light out? I've read anywhere from 4 to 50 starts before it clears itself. I've also read you can clear it by disconnecting the battery but have seen some cautions about doing that. On some cars, apparently, if you clear the codes by disconnecting the battery it will register some sort of "Unready" status on the computer for a certain amount of time and, if you take it in for smog test, it will fail due to that. I've got to smog this truck by 1 March. Is that long enough for it to clear by itself ... or for an "Unready" status to go away if I disconnect the battery? Any advice appreciated.
- posted
17 years ago