Cutout at 5600 rpm MS2

[citizen_insane]

Many people are using VR sensors without issue (myself included). Use the high speed crank logger to check, but based on what you're saying, it sounds like a CPS issue.

Have you already opened up your MS2 and turned both the VR regulation pots all the way counter clockwise? If not, do that first and then see if it improves it. If not, take your question to the msextra forums, they're the best people to ask about these kind of detail questions regarding Megasquirt.

[pazi88]

VR sensors have quite often issues with megasquirt. Grab cherry hall sensor, configure ms2 to use hall sensor and your problems are gone.

[Jaxx_]

looking at your log, your issue isn't spark related. It is, as you suspect, crank sensor related. Your log shows error 2, which is "missing tooth wrong time." You should have the crank sensor as close as damn possible. As I recall, it is a 2 wire VR sensor, so closer is generally better(as long as it doesn't rub). I have my M10's install at .030".

It is impossible to tell from this datalog what exactly is causing your sync loss issue. It could be noise related, or a hardware issue. You need to provide a high speed log of sync loss and regular cranking tooth trigger log.

[JIMBOkye]

0.028" is the plug gap. I'll check the CPS gap again tomorrow. I've read it is supposed to be about 0.040" (anyone confirm?), and it was last I checked (before MS went in).

[JIMBOkye]

To spec in Haynes manual, 0.028"

[digger]

MS has issues with the crank sensor what is the gap to the toothed wheel?

[m3boost]

Bit of background... Car '89 325is, stock motor.
MS2 kit from Dederic Motorsport installed because the car was cutting out at 5600 rpm previously and I have eventual plans to go to wasted spark and to eventually supercharge.

At this point I'd say I'm still very new to "tuning".

My previous thread on the 5600 rpm cut out is below:

https://www.r3vlimited.com/board/showthread.php?t=417320

Link to current tune and log (tunerstudio) showing the cutout (car in neutral in driveway):

https://drive.google.com/drive/folders/17KSCj9dYb_ykuQTbvEReqSIdLraiVsg_?usp=sharing

So after installing the MS2, the car was driving fantastically. But then all of a sudden, the cut at 5600 rpm came back! Cuts out every time at about 5600 rpm.

So, looking at the log it looks to me like the car is losing the crank position sensor because the RPM's are all over the place. But the MAP and AFR's are also all over the place (but maybe due to fuel cut...?) Could I be losing multiple sensors at once?

I've changed the Crank Position Sensor 3 times in a year. I feel like that shouldn't be the issue. Looking for some opinions before changing it again.

what gap on spark plugs?

[JIMBOkye]

Bit of background... Car '89 325is, stock motor.
MS2 kit from Dederic Motorsport installed because the car was cutting out at 5600 rpm previously and I have eventual plans to go to wasted spark and to eventually supercharge.

At this point I'd say I'm still very new to "tuning".

My previous thread on the 5600 rpm cut out is below:

https://www.r3vlimited.com/board/showthread.php?t=417320

Link to current tune and log (tunerstudio) showing the cutout (car in neutral in driveway):

https://drive.google.com/drive/folders/17KSCj9dYb_ykuQTbvEReqSIdLraiVsg_?usp=sharing

So after installing the MS2, the car was driving fantastically. But then all of a sudden, the cut at 5600 rpm came back! Cuts out every time at about 5600 rpm.

So, looking at the log it looks to me like the car is losing the crank position sensor because the RPM's are all over the place. But the MAP and AFR's are also all over the place (but maybe due to fuel cut...?) Could I be losing multiple sensors at once?

I've changed the Crank Position Sensor 3 times in a year. I feel like that shouldn't be the issue. Looking for some opinions before changing it again.