350z trigger issues

[michaelemira]

The car doesn't want to rev past 6000 rpm. I suspect its a crank sensor issue but I'm not sure what I'm looking at. The check engine light on the stock dash flashes when hits the limit. I made another log just revving from idle. It will rev past 6000 but trigger 1 appears to cut out and the rpm reads 0. I'll try replacing the crank sensor and see if that makes a difference. If anyone has some other advice I would greatly appreciate it.

PC Datalog - 2024-03-30 4;27;21 pm.llgx

RPM Limit Test.llgx

[Adamw]

A couple of common causes of trigger issues on the 350Z:

1.  if it has an aftermarket flywheel, there are quite a few that have the OD of the trigger wheel machined undersize and give problems at high RPM.  You can sometimes fix by cutting some material off the sensor flange to reduce the airgap.
2. Iron filings from ring gear/starter wear build up on the end of the sensor, if bad enough can cause errors.
3. The early "all plastic" crank sensor was unreliable, it was later revised.  The later sensor can be identified with a metal cap over the end.  If you have an early one and the points 1 & 2 above dont apply then it is probably worth replacing.  

[michaelemira]

2 hours ago, Adamw said:

A couple of common causes of trigger issues on the 350Z:

1.  if it has an aftermarket flywheel, there are quite a few that have the OD of the trigger wheel machined undersize and give problems at high RPM.  You can sometimes fix by cutting some material off the sensor flange to reduce the airgap.
2. Iron filings from ring gear/starter wear build up on the end of the sensor, if bad enough can cause errors.
3. The early "all plastic" crank sensor was unreliable, it was later revised.  The later sensor can be identified with a metal cap over the end.  If you have an early one and the points 1 & 2 above dont apply then it is probably worth replacing.  

1. I do have an aftermarket flywheel. I'll look into reducing the airgap.

2. Would clutch material also cause interference? This is a dedicated drift car so I do have a lot of clutch wear. 

3. I typically end up replacing this sensor at least twice a year. I have used both auto part store sensors, Z1 Motorsports and the Hitachi oem sensor. I have never seen one with metal on it.

I'm definitely thinking this is the same issue I have throughout the drift season. I did a bunch of modifications over the winter so I was worried it might be something else. I'll changed the CPS to confirm.

My next concern is trying to get this part to be reliable. Is the metal version actually available from anywhere?

[michaelemira]

Another new crank sensor fixed the issue. I'll keep buying spares for now. 

[Adamw]

On 4/2/2024 at 2:50 AM, michaelemira said:

I have never seen one with metal on it.

My info might be a bit out of date, that comment about the metal covered sensor was from a conversation with one of our old engineers who owned one.  

From a quick bit of research myself it looks like possibly the original unreliable plastic one was 23731-AL60C. 

That was superseded by 23731-AL60D which was the metal-covered one (Possibly Hitatchi# U11N03-REVS).

However, it looks like that has also now been superseded by 23731-AL60E which is back to a plastic body.  I dont know about the reliability of this revision.

But, since you do have an aftermarket flywheel, definitely keep the possibility of an airgap issue in the back of your mind.  I dont think you will find the correct air gap published anywhere, if you know someone with a stock one you could remove the sensor and measure the depth from the mounting face to the wheel teeth and compare to yours.