I've read that when a SES code is set, for example, the intermittent code 43 i get for no reason at all, the code must be read (flashed, whatever) and maybe disconnect battery or whatever to reset the ECM and clear the code. When that code 43 happens to me, the car goes into limp home mode, so i shut the car off, turn it back on, and the code is gone - the car runs fine again. Is this normal or is something wrong with my ECM? Thanks.

 

That is normal unless something is actually broken. The ECM sees an error from one of the sensors and throws a code. Once the conditions have changed (i.e. the sensor starts working again) then the light goes out. It still stores the code though so if you have a scanner you can still pull it up

 

What exactly is 'limp home mode'? I've heard of it, but don't know exactly what it is.

 

after so many starts, 50 i think, any set code is cleared if no condition exist to reset it. in other words a random condition will set a code but if it doesn't occur again it'll be lost after 50 starts

 

So if I tried to retrieve the code within 50 tries, I could, but the code is not gonna stay "set" and with the SES light on, right? This is normal then? Good, I wasnt looking forward to buying a new ECM.

On another note, what do you think could be causing my code 43 if nothing's going wrong, it comes out of nowhere, and all i have to do is restart the car to make it go away? Bad knock sensor or what?