Knock sensor problem..on '96 C280 HELP.

[ioang26]

Hey guys,
I bought my '96 C280 with "check engine" light on. I scanned the codes and it showed me PO327 which is Low input on knock sensor Bank 1. OK?
I replaced the knock sensor and erased the "check engine" light. After about 85 miles later the check engine comes back on with the same message about the knock sensor. What is the problem? What is wrong there?
I would greatly appreciate any help and advice.
Thank you in advance.

[jnenad16]

have you tightened it to specs? low input might be that the reference voltage is too low, which is regulated by the ECU. are there any driveability issues such as engine rough running at higher rpm's? have you checked your alternator's output?

nenad