Evo9 fluctation RPM

[Flint]

Hello!

Sorry for my English

Evo 9 car, 4g63 miveс, ignition system converted to direct spark, r35 coils, throttle DBW.
The problem is the strong bursts of the engine speed signal.
Physically, the revolutions jump a little but do not coincide with what the log shows.
The engine can operate normally for a long time, then it begins to throw revolutions very much, although the throttle valve behaves stably. It can be hard to set up after the bursts of revolutions have begun, although it is usually easy to engine start.
I assume that the problem is in the crankshaft position sensor.

Thanks for any help

Aleksandr

Log 2020-05-23 8;18;28 pm.llg Log 2020-05-26 11;45;15 pm.llg EVO 9 PCB.pclr

[Electredge]

I think your correct in assuming it is a Crank or Cam sensor issue.  I have had common failures with EVO cam sensors. 

 

[Adamw]

It is definitely a trigger problem but may not necessarily be a crank sensor, it could be the cam sensor or an intermittent connection or a noise issue.  

Next time it is playing up can you do a triggerscope and attach it here.  Here is how: https://1drv.ms/v/s!AiYbYlZQuRHPmidU5V2CmTcv6t2y?e=fGBwPM

[Flint]

Thanks for the support.
How to record a log, put it here.

[Flint]

I made a signal recording from sensors at different times. It seems that when the speed starts to jump something happens with the camshaft sensor or with its signal.

Trigger Scope Log 2020-05-28 6;22;34 pm.llg Trigger Scope Log 2020-05-28 6;22;09 pm.llg Trigger Scope Log 2020-05-28 6;21;51 pm.llg Trigger Scope Log 2020-05-28 6;20;58 pm.llg Trigger Scope Log 2020-05-28 6;20;27 pm.llg Trigger Scope Log 2020-05-28 6;13;10 pm.llg Trigger Scope Log 2020-05-28 4;54;44 pm.llg

[Adamw]

Yes, definitely looks like the cam sensor.  We can mostly rule out wiring as if there was a bad connection we would see the signal go to 5V, but yours drops to 0V when it is playing up. It would pay to check that the chopper disc hasnt come lose on the end of the camshaft but otherwise I would try replacing the cam sensor.

[Flint]

Thank you so much!

Another question, I noticed there is no signal from the camshaft sensor vvt. Tell me how it should be configured?

[Flint]

replaced the exhaust camshaft sensor and the problem went away

[Adamw]

Are you still getting no cam position reported for the VVT intake cam?  Your DI settings look correct so I would probably start by running the cam angle test for the LH inlet cam and use the results from that test to confirm your DI offset is correct.  Instructions are in the help file, G4+ ECU Tuning Functions > VVT Control > Tuning VVT Control > Cam Angle Test.  Use a test pulse count of 4.

[Flint]

Yes, Adam, it wasn’t possible to get a signal from the camshaft intake sensor. It seems he is not okay, ordered a new one.
I read the help file, tried to check the cam angle, but there is no signal from the intake camshaft sensor. I set the test pulse counter to 2, I thought that this means the number of petals?

Do I need to set the numbers in the VVT inlet target table in the idle zone when I do a cam angle test?

[Adamw]

14 minutes ago, Flint said:

I set the test pulse counter to 2, I thought that this means the number of petals?

Yes there are 4 teeth on the Evo 9 intake cam.  (only 2 on the exhaust cam).

 

 

15 minutes ago, Flint said:

Do I need to set the numbers in the VVT inlet target table in the idle zone when I do a cam angle test?

No, The cam is forced to the home position during the angle test.  You do need to be above the RPM and ECT lockouts but yours are set low so that should have been fine.

[Flint]

Oh, got it. thank