p.i.engineer

i've recently replaced both knock sensors and a leaking oil pressure sensor.

P0332 code has popped up again after about 100 miles.

i've checked both knock sensors and am getting 99.8k ohm on each. I've also checked for continuity from the knock sensor harness plug to the ecm connector.

does anyone have any thoughts on what else i should check or missed?
thanks

repairman54

Did you use GM sensors? Aftermarket sensors are not reliable.
If you used GM sensors then it's most likely a harness or ground issue. Use a dedicated electronic cleaner/lubricant on all the connectors. It doesn't take much of a poor connection to trigger codes. Ohm checks on sensors may not be reliable as they are not under the systems ''load''.

p.i.engineer

i did not use OEM. thank you for opinion. I may just bypass with resistors.

hanky

I believe your logic may be a little faulty, why ?
Some sensors deliver varying info and could render the system totally inoperable
.It is great when you can substitute simple values for some sensor that provides signals measured by resistance only. There are only a few and they involve redundant receipt of info. We never know when someone will come up with a better way to overcome these problems, but I believe a little more research might be required

As you are aware, the electronics in today's vehicles obtain info in many forms . Reliable PWM signals are not that easy to substitute as is the return info the monitoring computer module processes. What do you think?

p.i.engineer

It was a free car and I like to tinker. I doubt the knock sensor is generating a pwm value with only 1 wire going to it. I could be wrong, not afraid of messing with it.

repairman54

I would put a GM sensor in. Add a ground wire to the engine and verify PCM grounds are good as grounds are known issues in older vehicles. Single wire sensor, all engine sensors for that matter, need a great ground as engine movement under load could be part of the problem.
Knock sensor pulls timing out of the engine when sensed. It is in play more than you think as PCM pulls out timing from its maximum setting in its maps according to what the sensor is reporting to prevent pre ignition. Part throttle pre ignition was very common in all makes that's why the knock sensor came into common use.

p.i.engineer

that's on my list, to reverify grounds and check resistance from ecm connector to ground.

pruitt09@att.net

I am having the same problem with my 2001 suburban with 118,000 miles on it, replaced both knock sensors with Acdelco along with new Acdelco wiring harness, have done this job twice now for the reason of being concerned that I may have overtorqued the sensors, still getting the check engine light and P0332 code after about 30 minutes to 1 hour of driving. I have also pulled the Power Management Computer and sent out to be checked, it was determined faulty or non repairable so I purchased rebuilt from them, the rebuilt PCM did solve an issue that I was having related to loss of power when taking off from a stand still (this only happed a small number of times but very dangerous)……Very frustrating after doing all this work and still getting CEL along with P0332 code, my next thought is to check with GM to see whether or not a software update could solve any of these issues…..I am the original owner of this 21 year old vehicle and have done most of the work on it myself therefore not making it into a Chevy repair center where they may have checked it for software updates that may be needed…….Any thoughts or ideas from anyone would be greatly appreciated.

p.i.engineer

i ended up tying bank 1 into bank 2 and my check engine light turned off. good enough for me for now.