neal64ss

iTrader: (1)

Put a 5.3/4l60e in my 64 chevelle. Recently installed new American Autowire "classic update" wiring harness & new PSI conversions engine harness. Also recently installed new AC delco 41-110 plugs, AC delco wires, new MAF sensor, both knock sensors, & knock sensor wiring harness.

Car runs great, idles smooth, no drive-ability issues.

I keep getting the following 3 OBD II codes.
- P0101 (Mass or Volume Air Flow Circuit Range/Performance)
- P0327 (Knock sensor 1 circuit low)
- P0332 (Knock sensor 2 circuit low)

I have verified the correct resistance for both the Knock sensors with a multimeter.

I am at my wits end trying to figure this out.

neal64ss

iTrader: (1)

Anyone?

redline2k

iTrader: (9)

It is common for the pigtail to go bad on the knock sensors

1964SS

iTrader: (1)

Yep, As said above the pigtail could be your issue. I would measure each sensor with an ohm meter to verify they are within spec and then measure at the end of the pigtail or even at the ECU pin locations to verify the signals are getting all the way back.

neal64ss

iTrader: (1)

I replaced the "pigtail", or knock sensor wire harness. All wires on this vehicle are new. I have checked the knock sensors and confirmed the proper resistance.

1964SS

iTrader: (1)

Check the signals at the ECU from both knock sensors. If they meter good then your ECU itself has an issue.

neal64ss

iTrader: (1)

This is what I have been suspecting. Is it common for an ECU to have issues? What is involved in replacing an ECU. Can I just buy one and get it retuned for the year and make of the donor vehicle?

neal64ss

iTrader: (1)

Problem solved.

I replaced both generic brand knock sensors with delco brand and that resolved the knock codes. Replaced the generic MAF sensor with a new Delphi MAF and that code is now gone as well. The difference in build quality on the MAF was astonishing as I compared the two.

Thanks to all who responded and helped to point me in the right direction.