Chevy 5.3 p0327
I’m working in a 2005 GMC Sierra 1500. Mil was on and p0327 was the code. I changed both knock sensors and the harness And code keeps returning. I’ve checked wiring prior to sub harness abs seems fine. Any pointers? I appreciate the help.
There is a thread on here regarding that code and op has replaced everything including the PCM and multiple knock sensors. I say scope the signal and they should be the same for both signal and low ref wires. If they are somehow off, the sensor may be faulty. Clean the surface on the block as well. The manual doesnt show a ground contact but those sensors that bolt on usually grab the ground…
Ohh. Because i had the same problem with a co worker that he installed some autozone brand and the code was still coming up and i cheked them and they where fine but the thing is that every knock sensor have their own sensivity. On difrent specs and. I told him to order. ac delco and he did so that fixed the problem. hope the info helps
Hi Jim, Use genuine GM sensors and harness per TSB info and torque them to 15 Ft Lbs. P0327 is indicating the front O2 sensor.
Hi Jim, That was according to my info. What are you using?
Hi Jim, There is also a GM truck enthusiast website among others that can give you a lot of good information about the TSB and issues with the knock sensors.
Jim, I have to agree with the others. Go with OEM parts. I I have ran into the exact issue with aftermarket sensors. Before you resealing the upper plenum go to PCM live data on your scan tool scroll to live sensor. With ignition on tap onl sensor with a wrench to see if it is toggling on your scan tools live data. If it still won't toggle ohm wiring from harness back to PCM. That may save you…
I’d start with dealer or Delco sensors. They are so sensitive GM used to use gold plated connectors.
If you changed both with same brand and are still coding for same sensor-unlikely it's a sensor issue. Your header states 5.3, but body states 4.3, which is it? Unless it's coding with key on engine off, don't overlook it may be a mechanical issue and sensor is actually detecting noise that it cannot eliminate with ignition timing. If you still cannot confirm- switch circuits from bank 1 to bank…
We dealt with this on a similar truck years ago. The tech overtorqued the sensors. Happy trails,
GM has had issues with their knock sensors systems. The last time I encountered one was with a trailblazer with a V-8 and after replacing them twice with aftermarket, I installed Genuine GM from the dealer,it came with the harness and advised to torque to specs. There are quite a few TSBs on that issue as well.
Everyone else sounds like they nailed it, I'm just here to stress the importance of the torque spec on these. I've been there, done that.
The plug is right on top of the intake. Take some jumpers and swap the wires. If same code comes back you have a problem with harness. If p0325 come you have a prob under intake, harness or sensor
I agree with everyone I just wanted to say that the torque on these sensors is very important!
Is there any engine knock or mechanical noise present?