What went worng Need help fast
Thread Starter
Burning Brakes
Joined: Nov 2005
Posts: 1,211
Likes: 2
From: Dumas Arkansas
What went worng Need help fast
I was driving aroung about to leave town when the SES light came on and figured it was code 43 knock sensor. Well I drove back home and got the paperclip to check and it was 43. That was the only code that popped up in the display.
Now after pulling the clip out and trying to crank the car she died and it feel's like she starving for fuel. I tried to back up but it died again. This has never happend before. Just clueless to what to look for. All the plug wires looked ok. As a matter of fact when I turn the car on the two fans that come on when you do a paperclip check come on as well. I can hear the fan sound when the car is cranked.
Now after pulling the clip out and trying to crank the car she died and it feel's like she starving for fuel. I tried to back up but it died again. This has never happend before. Just clueless to what to look for. All the plug wires looked ok. As a matter of fact when I turn the car on the two fans that come on when you do a paperclip check come on as well. I can hear the fan sound when the car is cranked.
Burning Brakes
Joined: Nov 2004
Posts: 781
Likes: 0
The CODE 43 can put the ECM into 'limp home' mode, which will run both fans (regardless of water temp), richen the fuel trim, and conservatively retard timing. Any of these conditions should not keep the car from starting, or running, but you never know with these cars. I would fix the knock sensor problem first, then trouble shoot the dieing problem if it continues.
When a knock sensor fails it usually looses all of its internal electrical resistance and is pretty easy to diagnose. Take an OHM/VOLT meter (preferably a quality digital meter), set it to read OHMs, unplug one of the knock sensors and stick the red probe into the nipple connector in the end of the knock sensor and ground the black probe on the very outer edge of the knock sensor body (or on the engine block itself as near to the sensor as possible). The LT1 knock sensor operates correctly with around 3.89 ohms of resistance, so a reading over about 4.5 or under 3.0 is considered unacceptable. A reading of ZERO ohms is obviously a total failure and will be the cause of your CODE 43. Of course, check both sensors, on both sides, just to make sure. A new GM knock sensor is around $30 and I will post the '92 part number later. They double as the lower engine block plugs and will leak coolant when loosened and removed, so be prepaired for a wet, messy job. Maybe have a friend help to plug the hole with their finger while you switch the sensors (this will keep coolant loss/mess to a minimum).
When a knock sensor fails it usually looses all of its internal electrical resistance and is pretty easy to diagnose. Take an OHM/VOLT meter (preferably a quality digital meter), set it to read OHMs, unplug one of the knock sensors and stick the red probe into the nipple connector in the end of the knock sensor and ground the black probe on the very outer edge of the knock sensor body (or on the engine block itself as near to the sensor as possible). The LT1 knock sensor operates correctly with around 3.89 ohms of resistance, so a reading over about 4.5 or under 3.0 is considered unacceptable. A reading of ZERO ohms is obviously a total failure and will be the cause of your CODE 43. Of course, check both sensors, on both sides, just to make sure. A new GM knock sensor is around $30 and I will post the '92 part number later. They double as the lower engine block plugs and will leak coolant when loosened and removed, so be prepaired for a wet, messy job. Maybe have a friend help to plug the hole with their finger while you switch the sensors (this will keep coolant loss/mess to a minimum).
