Service Engine Soon light on AGAIN.......
#1
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Service Engine Soon light on AGAIN.......
i walked out to the bonne today and was greeted with my sirius satellite radio saying UPDATED on the screen so i had that working now then i look down at the dash and i see the SERVICE ENGINE SOON light on and im like "here we go again" to myself, i pulled the code and it was code 43 Electronic spark control circiut or Knock sensor problem
this is the second time this code has randomly shown up in the last few months, once with the magnavox ignition and now with the delco. so im thinking its the knock sensor more than the spark control unit. would the knock sensor cause a random minute of heavy misfiring at idle and as soon as you tap the gas it goes away and may or may not come back at idle. cuz my car does this. i swear this thing has the worst case of pms ive ever seen in my life.
*edit* also i was getting a code for system lean a few weeks ago. it went away after a reset and never came back but would that have anything to do with this?
this is the second time this code has randomly shown up in the last few months, once with the magnavox ignition and now with the delco. so im thinking its the knock sensor more than the spark control unit. would the knock sensor cause a random minute of heavy misfiring at idle and as soon as you tap the gas it goes away and may or may not come back at idle. cuz my car does this. i swear this thing has the worst case of pms ive ever seen in my life.
*edit* also i was getting a code for system lean a few weeks ago. it went away after a reset and never came back but would that have anything to do with this?
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Disconnect the battery for a minute and blank all of the codes... Reconnect the battery... Ground the diagnostic pin in the ALDL, turn the ignition on( engine off ) and pull the codes again... You should only get a code 12.... If you get no codes pull the jumper, start the car and drive it and if the SES come back on check the codes again( engine off )... After you do that report back..
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#5
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Maybe on the knock sensor, but it would cause the ECM to pull timing rather than a misfire. You can sometimes get the engine to stumble by tapping on the engine with a wrench or hammer. The knock sensor will see it as knock and may pull timing. It depends how sensitive it is. If it is installed too tightly, it may be overly sensitive. You don't have a knock at idle that goes away at higher rpm maybe? You could also have a problem with the harness that runs across the front of the engine. It connects to the cam and crank sensor and also carries the "EST" or electronic spark timing signal, to the ignition module from the ECM. The car starts using programming in the ICM under the coils only, and then when the rpm comes up the ECM sends a signal to overide the module timing and runs under ECM control for the timing. If the EST signal is lost, the engine reverts to the base timing in the ICM, sometimes called limp home mode, that has fixed timing of about 10 degrees advance. The engine will run, but performance will suffer. Maybe an intemittant connection or insulation rubbed through?
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Originally Posted by 2seater
Maybe on the knock sensor, but it would cause the ECM to pull timing rather than a misfire. You can sometimes get the engine to stumble by tapping on the engine with a wrench or hammer. The knock sensor will see it as knock and may pull timing. It depends how sensitive it is. If it is installed too tightly, it may be overly sensitive. You don't have a knock at idle that goes away at higher rpm maybe? You could also have a problem with the harness that runs across the front of the engine. It connects to the cam and crank sensor and also carries the "EST" or electronic spark timing signal, to the ignition module from the ECM. The car starts using programming in the ICM under the coils only, and then when the rpm comes up the ECM sends a signal to overide the module timing and runs under ECM control for the timing. If the EST signal is lost, the engine reverts to the base timing in the ICM, sometimes called limp home mode, that has fixed timing of about 10 degrees advance. The engine will run, but performance will suffer. Maybe an intemittant connection or insulation rubbed through?
hmmmmmmm.
#7
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Bad connections are allways suspect on intermitten codes.
I would reset it like Jr said and also remove the ICM connector and tighten up on the sockets. (takes patience and a tiny screwdriver). Then put it on and off a couple times, apply dielectric grease and see how it goes.
I would reset it like Jr said and also remove the ICM connector and tighten up on the sockets. (takes patience and a tiny screwdriver). Then put it on and off a couple times, apply dielectric grease and see how it goes.
#8
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misfire
One other thought:
A bad plug or wire could cause a random misfire that engages the knock sensor.
The ECU then retards the timing until the knock goes away.
A bad plug or wire could cause a random misfire that engages the knock sensor.
The ECU then retards the timing until the knock goes away.
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