I have a 91 Z28, 5.7 with the speed density computer. I have been getting a code 43 which is either a knock snesor or the esc. Where is the ESC module on the speed density car?

Ty for the help in advance!

 

I usually check the knock sensor first with that code, what most GM computers do is send out a .5 volt reference signal to the knock sensor, pull the connector and check that the .5 is there first(key on). As long as the reference voltage is there plug it back in and "back probe" the pigtail with the multi meter to see what the voltage is plugged in...the knock should pull the voltage down to .25 or so volts if the sensor is good(key on). try this first before you start throwing darts at the problem.

 

The "ESC module" on a SD car is actually internal to the ECM. If the knock sensor and wire are both good, then the ECM itself must be bad.

Make sure there's no sealant/thread tape on the knock sensor as it grounds through the block.

 

Is your tan wire with black stripe, single weather connector, connected? The connector you must disconnect before setting timing... If it's not it will cause this code too.

 

tan/blk wire = code 42,not 43.

 

Ooooops...my bad!
Flow chart:
- AEngine above 67*C does a scan indicate a value of knock retard between 4* and 20*?
= iF YES, disconnect the knock sensor with ignition ON use a DVM between harness circuit #496(GF9 at the ECM and the end of the knock sensor wire)
voltage on the wire should read between 4 & 6volts.
Does it?
If yes, check the resistance of the knock sensor to engine block. It should be between 3300 and 4500ohms.
If less than 4 volts, circuit #496 is open, or faulty ECM.
If over 6volts, see if the knock wire is too close to a spark plug wire inducing voltage. or faulty ECM.
If YES resistance is good, see if the chip is firmly seated in ECM, see if harness connector is in good condition. Replace chip.
If NO resistance is bad, faulty knock sensor.

 

Where's the terminal B7 on a 7730 ecm? Looking at my ecm, I have 2 for chip burning purposes, I see a yellow terminal on the Rt, and two black ones to the left. I do not see a B on either terminals. I read somewhere to check the voltage at the B7 terminal too.

Thanks for the advise!

Also, please clarify this;
If less than 4 volts, circuit #496 is open, or faulty ECM. 496 is open??? What are you saying here? short in the system? Bad sensor? Just want some clairfication incase I need to chase anything