DIC code PO327 Help please!!

[porschegreguk]

Hi I Live in England and have a 98 C5. The check engine light is on and the DIC code has come back as PO327. This is one of the knock sensors on the engine. The car came to me with an aftermarker exhaust that was home built and was leaking. I thought that mayby the exhaust was setting off the sensor so I reinstalled the original system. I reset the computer but within a few days the light has come back on. I'm assuming that this means I have a bad sensor? My questions are this


1. Where is this knock sensor located?

2. How difficult is it to replace?

3. Do I need special tools to do this?

4. If it is buried inside the engine where would I get a workshop manual
with drawings, and instructions to do the job?

5. How long should it take to do it?

6. What is the part number and where would be the best place to source
the sensor from?

I would greatly appreciate any help. Best regards Greg

 

[DRTH VTR]

Welcome to the CAC!

Are you using high octane fuel?

 

[Mr. Lucky]

I see that this is your first post. Welcome to
The knock sensors themselves are easily removed using standard hand tools. It is necessary to remove the intake manifold first. Once you do so, the two sensors will be in plain view, in the valley cover on the top of the block.
[Ref. http://www.lingenfelter.com/pdf/Intercooled%20SC%20manual.pdf steps 100 &101]

Do not assume that the sensors are necessarily bad. Bad (or too-low octane) fuel could cause the problem, as could too much timing, or mechanical noise being detected as knock (e.g., "false knock," such as: a bad bearing, squeaking pully, or even certain exhaust rattles). Just take a systematic approach, and it should make a good weekend project.

Also, in case you need it, here is the troubleshooting info for that DTC on model year 1998.

HTH!

 

[99WhiteC5Coupe]

There was a TSB regarding knock sensors (including the 1998 C5). You can view it here: http://corvetteactioncenter.com/kb/question.php?qstId=261

Good luck.

 

[porschegreguk]

Thanks for the welcome! The lowest octane fuel over here is 95, so not a problem! The car isn't pinging at all. After I have reset the computer it will somtimes be fine for 50 miles and other times will come back on when it is just sitting there idiling. Will have a look for exhaust leaks and anything that might be rubbing and making a noise. Many thanks for the replys. Best regards Porsche Greg

 

[DRTH VTR]

Thanks for the welcome! The lowest octane fuel over here is 95, so not a problem! The car isn't pinging at all. After I have reset the computer it will somtimes be fine for 50 miles and other times will come back on when it is just sitting there idiling. Will have a look for exhaust leaks and anything that might be rubbing and making a noise. Many thanks for the replys. Best regards Porsche Greg

Isn't the octane rating system different in England? There are multiple systems for scoring octane rating. In the US, we have to buy the highest octane fuel commonly available at the pump. Might I suggest a high grade fuel for one tank to see what happens? The Corvette will run on "regular" gas, but at the expense of performance and a risk of engine damage.

 

[Hib Halverson]

My guess is that, even if the U.K does not use the R+M/2 method of determining octane, 95 oct fuel (be it research or motor octane) is good enough, besides, there are no symptoms of audible detonaton.

DTC0327 sets when the PCM receives a KS signal frequency either lower or higher than expected for a duration of less than three seconds. One symptom that is strange is that the DTC is setting with the engine idling, which, according to the Service Manual, can't happen.

DTC0327 could be caused by either engine mechanical problems (like a "rod knock") or severe detonation, both of which one could hear and were not cited as symptoms.

To properly diagnose this problem you need a factory service manual for MY98 and a DMM. I would use the service manual diagnostic procedure because it is possible to fix this DTC without removing the intake manifold.
Factory manuals can be ordered on-line form the Helm Inc. web site.

The repairs will be either to
1) locate and fix a wiring and/or connections problem in the wiring harness
or
2) replace one or both KSes
or
3) replace the PCM which also requires reprogramming.