gafirefighter

First, let me say thank you for allowing me to join. Looks like a great forum and I always own some GM vehicle. That being said, here is what I have going on…

I have a 2002 Tahoe. It recently began throwing codes from lean bank one and two and for the rear knock sensor. After reading on the forum a bit, I decided to replace the intake gasket and both knock sensors. I also replaced the knock sensor harness at the same time. The intake gasket was the upgraded Felpro and the knock sensors where Masterpro from O’Reilly Auto.

I drove it about 90 miles and the code P0332 for the rear knock sensor appeared again. I cleared the code and within 12 miles it came back on. I again cleared the code, and it stayed off. For about 30 miles it showed a pending code in my reader, but it never caused the CEL to return. After those 30 miles the pending code went away.

Today, the CEL again returned with the same P0332 code. It has been 351 miles since the pending code disappeared. I thought that maybe it had gone away for good, but that was obviously not the case. I have read a lot about this, but wanted to check with some other people before I pull the intake off again.

The only thing I can think of to do would be to return these sensors and purchase different ones. Any suggestions or information would be greatly appreciated.

Thank you,

Adam

in2pro

Welcome to the forum.
Its hard to say, I know its a bit of work but it might be worth replacing the rear knock sensor as a sanity check, I would strongly recommend going with the OEM AC Delco or Delphi sensor(s) as you got this many years out of the OEM going cheap on a hard to replace item can have its consequences....

cleveland63b

anything electrical I always go OEM, you can do circuit testing and continuity checks on the sensor to be sure but I wouldn't be surprised if OEM sensors fix it. Did you silicone around the boots on the knock sensors?

gafirefighter

I used electric grease on the connections. Luckily they have a one year warranty. I'll pull them out and return them. Nothing like doing all that to immediately have the code return.

gafirefighter

Tonight I am going to pull those sensors and return them. I will order a set of OEM. Amazon is selling them cheaper than aftermarket. Will the intake gasket be alright to continue to use. Brand new metal and rubber Felpro upgrade.

in2pro

Don't put anything on the actual metal contact itself only the boot/sealing surface die-electric grease or silicone grease is not conductive and will cause electrical problems.... its sole purpose is to seal out moisture and help prevent corrosion by keeping the electrical connections dry...
I do applaud the extra step to ensure a optimal connection... if you wanted to you might consider getting an electrical contact cleaner and clean each side of the connection prior to assembly to ensure all grease is removed from the metal contacts, use a q-tip to apply the grease to the boot seal only...
There are electrically conductive paste or "grease" available but it has to be used sparingly and very accurately to prevent shorting or signal contamination.

gafirefighter

Thank you all for the great information. I am about to remove the sensors again. I will be ordering the OEM parts tonight.

Adam

gafirefighter

Do you all think that I will be alright with the Dorman harness, or should a buy an OEM harness also?

Thanks,

Adam

ArcLighter

Recently bought this 2003 Suburban -no check engine light- added tankful of 93 octane, non-ethanol gas, check engine light came on; rebuilt the transmission (probably had neg batt terminal disconnected/clock not set) and no check engine light. Gas down to half tank, filled it up with reg. 10% ethanol fuel - check engine light came on. Autozone showed P0332 knock sensor.
Wondering if the computer is sensitive to different octane fuels and especially to the non-ethanol 93 octane....any ideas?

cleveland63b

its possible but not likely, especially since higher octane reduces spark knock. If you are comfortable running an ohmmeter I'd say its time to check them, or take the intake off and inspect for corrosion.