the A/T hacked on your car can in fact cause ECU to go nuts.
the ECU (PCM) monitors 2 wires (of the many)
1: THE START LINE (STARTER ACTIVE.) most go 0v after release key, at ECU actual input pin.
2: THE A/T BOX "PRNDL" SWITCH STATE, (my guess is this was only hacked, but IDK.)
IF ANY OF THOSE ARE WRONG , THE ECU WILL FAIL TO IDLE OR EVEN START CORRECTLY
when you shift to drive the ECU changes idle profiles radially, if you lie to this pin wire, the ECU will do crazy things. (or fail to inject, IDK firmware that deep on any car made)
as they say fix the easy stuff first. for sure this.
the ECu sees you keyon, and boots and glows the CEL (does it), the sees the starter go active , then sees the RPMs go way over 300 to 500 rpm and set the I am running flag.
then the ECU injects based on all inputs. even coolant temps.
the hack was to tell the ECU you are in park (a lie if in drive)
and if you do that in drive idle will fail. for sure.
after all I do not know the level or extent of the hack but , is all very serious. (or sure starting in gear, and danger to others and worse)
what is a rule on EFI try not to fool the ECU too much, many just go nuts, or even hunt the ISC IDLE speed, like mad like the 89-95 do with vacuum leaks.
the ECU (PCM) monitors 2 wires (of the many)
1: THE START LINE (STARTER ACTIVE.) most go 0v after release key, at ECU actual input pin.
2: THE A/T BOX "PRNDL" SWITCH STATE, (my guess is this was only hacked, but IDK.)
IF ANY OF THOSE ARE WRONG , THE ECU WILL FAIL TO IDLE OR EVEN START CORRECTLY
when you shift to drive the ECU changes idle profiles radially, if you lie to this pin wire, the ECU will do crazy things. (or fail to inject, IDK firmware that deep on any car made)
as they say fix the easy stuff first. for sure this.
the ECu sees you keyon, and boots and glows the CEL (does it), the sees the starter go active , then sees the RPMs go way over 300 to 500 rpm and set the I am running flag.
then the ECU injects based on all inputs. even coolant temps.
the hack was to tell the ECU you are in park (a lie if in drive)
and if you do that in drive idle will fail. for sure.
after all I do not know the level or extent of the hack but , is all very serious. (or sure starting in gear, and danger to others and worse)
what is a rule on EFI try not to fool the ECU too much, many just go nuts, or even hunt the ISC IDLE speed, like mad like the 89-95 do with vacuum leaks.
http://www.fixkick.com