VX keeps blowing Crankshaft Position Sensors every 6+ months (With Error Code: P1372)

[Jonathan Meele]

Hi all,

My Holden VX Series 2 keeps blowing Crankshaft Position Sensors (the one behind the harmonic balancer).
I'm on about the 3rd or 4th sensor in a few years. The first one occurred approx 6+ years ago but within the last 2 years (Give or take) my car has blown another 2-3. Reason I know it's the Crankshaft Position Sensor is because I run a scan tool which shows fault code P1372. Last one occured in January this year. Upon having the Crankshaft Position Sensor replaced it works fine again.

It's starting to become vexing as it's costing me $250+ each time to get it replaced via my local mechanic and when the issue occurs my car stalls which is extremely worrying considering I could be anywhere. My mechanic apparently sourced the most recent replaced sensor elsewhere (Would have either been Burson or Repco) to try to rule out the possibility of a cheaply manufactured sensor via the previous supplier, but it has occurred again 6+ months later.

The only difference between the last few times and this timeis that my car will not start regardless of what I do, it cranks but doesn't start. Previously my car would stall only when it was hot (At operating temperature), I'd wait 1+ hour for the engine to cool down and I would be able to start it again and get about 5km's before it stalled again. This time it stalled, I was able to start it again and get it home and now it will not start again. I have tried disconnecting the battery overnight and connecting it back up again to see if it would miraculously start working again, but of course that was wishful thinking.

Is there anything I'm overlooking here or any advice that can help? Any tricks or tips? Is there a hidden fuse somewhere that I should be checking?
The only thing I haven't tried is spraying the connections with Electrical Contact Spray but it's highly unlikely that will work.

Thank you in advance.

Edit: Before anyone recommends that I learn how to replace Crankshaft Position Sensors myself, unfortunately I'm not skilled enough to do it.... I tried to do it myself when the first one occurred 6+ years ago but I couldn't get it off using a breaker bar and a guide on this forum.

 

[lout]

sensor behind harmonic balancer is crankshaft position sensor
which is what your fault code indicates
now codes do not mean throw parts
they mean measure that circuit and determine what is wrong
wiring connections are a known fault
as is the dfi module

 

[Jonathan Meele]

sensor behind harmonic balancer is crankshaft position sensor
which is what your fault code indicates
now codes do not mean throw parts
they mean measure that circuit and determine what is wrong
wiring connections are a known fault
as is the dfi module

Thanks, I have corrected it to Crankshaft Sensor, I get them mixed up but yes I'm 100% referring to the Crankshaft sensor (Behind the harmonic balancer).

You're basically saying that it may (or may not) be the wiring as opposed to the sensor? I don't suppose the loom / wiring in question is easy to replace?

If it was the DFI module would it throw any other codes and would a DFI module just prevent the engine from turning or would it be an intermittent issue with performance rather than not turning over?

 

[lout]

the plug connectors to the sensor and the dfi are both common to fail
aftermarket crank angle sensors have thinner terminals and often result in intermittent problems
the plug connector to the dfi often melts and burns a little
the sensor sends the signal to the dfi
which then controls timing until engine starts and then bypasses signal to ecu

 

[mirrabucca]

There is a great write-up on here (somewhere) that describes how the CAS works and how to trace/check wires.
The wires from the CAS to the DFI are known to fail, especially at the age these cars are now.
I had the same issues with my VX's CAS a few years ago. Original one failed once, then a few weeks later - again. Then it became more regular.
Waiting for it to cook worked but it soon became too long to wait. It dies once in a shopping centre par park. I couldn't wait so I doused it with water. That fixed it for long enough for me to drive home. I had bought an ebay one ready to fit. That worked for all of 10 minutes. It was ok at low revs but over 3500-ish it woulf fail. Code 1361). So I bought one from Repco (sealed in its box). THat turned out to be the same brand as the ebay one! I went to Holden and bought a real one. Fitted. No more problems.

 

[RWD4ever]

Crank angle sensors unfortunately don't have much temperature margin. They usually fail when it is over 40 degrees in summer. If yours are failing every 6 months, I would suggest it is not the sensor, but elsewhere.

 

[Bay 13]

250 steep, my cheap Ebay one been good for over a year, go to a different mechanic.

 

[Immortality]

Or maybe it's a problem with the DFI module as both the crank and cam sensors are run via the DFI (it supplies power and ground etc).

In all my years of owning V6 Commodores I've never had a CAS fail except a VN one that touched the balancer and was physically damaged. The big difference between here in Aussie are the ambient temps. I've also had a new genuine CAS sitting on the shelf in the garage since forever (to keep Mr Murphy at bay).

 

[chrisp]

Perhaps not for the fainthearted, but there is an excellent step by step diagnostic procedure on this website - https://easyautodiagnostics.com/gm/3.8L/ignition-module-and-crank-sensor-test-1