89 RS
305 E 5.0L TBI

Code 43-Electronic Control Module has detected an electronic spark control input signal for too long a time period.

While at Ivy Tech this morning when trying to start my car it took 3 trys and just kept dying everytime. while driving home i had a SES light and my timing retarded. pulled over and restarted the car. the light went away and the timing was back to normal. went to check knock sensor reving the car in park and knocking on the block around the sensor. rpm's dropped saying that the sensor was good. SES light has came on before 4 months or so ago and just now came back. The car has had problems starting all day after sittin half an hour or more. Could this be the knock sensor on its way out...comming in or out or do you think it is more computer related???

Autozone info on code 43....

If the timing changed/rpm dropped the cause of code 43 is intermittent.... no more info on if it did drop what the causes could be....

 

is your ses light a hard light, not going out? if so, you could have a bad wire or not even getting voltage to it, not a bad knock sensor. it's easy to check the voltage and/or resistance of the sensor first...

if you disconnect the lead to the knock sensor, with key on, you should read 4-6 volts. if no voltage (as was my case) that is probably the culprit. if it's over 6V or less than 4V, probably shorted to ground or bad ecm.

if you have voltage, check the knock sensor by reading the resistance to ground. should be 3300-4500. (may be diff for a 305, i dunno).

if all that is good, then possibly the prom in the ecm.

also (and you may already know this) if you have to change the knock sensor, it is also the drain plug on that side, so you'll have coolant coming out at ya...

 

No it is not a hard light...sometimes when tyring to start almost always takes 3 times and after driving sometimes i get the SES light making the timing retard and sometimes i dont get the light or the retard. This problem always seems to be happening with a cold start. The car starts each time but just stumbles and dies and giving some gas doesnt help at all making me believe that it IS the sensor not sending the signal of the initial start up knock. I cant think of why it would only happen with a a cold start??