Vvti 2jzgte no start after warm

[Teigster]

Having some issues on my engine not being able to fire up immediately after a shutdown. 

Prior to coming here, I scoped both cam and crank sensors discovered a weak cam sensor scope and adjusted the arming thresholds on the trigger. Still had issues. Replaced the cam sensor with a new one. Same issue.

Changed out the crank sensor today as it had a trigger failure during idle. (I was not able to poke my head into the bay enough to inspect the reluctor wheel teeth. I was very careful not to damage it during the build) the engine idles fine currently but still issues trying to fire after warm unless I have 5-7 minutes to sit. 

 

Attached logs and tune. I think I incorrectly saved the scope wrong but I did take a picture.

 

The startup issue has been present since the build. The failing cam sensor was after several thousand miles.

 

 

Teigons Current Tune.pclr

[Adamw]

Can you do a trigger scope while cranking next time it wont start.  It is showing zero RPM so something odd with the trigger.  When was this ecu purchased?  

[Teigster]

The ecu was purchased sometime during June or July of 2019.

Unfortunately I could not get it to repeat the symptoms this morning. It fired Everytime without hesitation. (First it's done this since build) 

The image attached is one of the warm start ups I have three other images that share the same characteristics. All fired without hesitation. 

Any thoughts on this Adam?

[Adamw]

In your log above named "***restart attempt".  For the two restarts at the end it showed trig 1 signal but no trig 2 signal.  It showed the arming threshold was set to about 0.78V on trig 2 at the time that log was taken (it has obviously since been changed since your map now shows 0.2V).   

You can see in the last trigger scope pic you attached the trig 2 is only outputing about 0.4V so the 0.8V arming threshold would have been too high to allow the signal through.

[Teigster]

Thanks for working on this Adam, doing my best to get the issues to arise.

Alright went for a drive arming threshold at .2 for trig 2 on 0 rpm. 

Drove fine for a mile. Had a weird misfire issue at the stop light when getting going. Kept it alive. Did another mile died at the next light fired right up though. Got to my shop, shut it down and fired up just fine. 

After getting back home attempted a shutdown restart and the issue finally arose again. no start.

 

Attached logs and a scope image on the failed refire attempts.  Had to zip the log was a bit oversized.

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[Adamw]

Attachment is not showing.  If it is too big you can share a like using google drive or onedrive etc.

 

[Teigster]

On 8/22/2021 at 4:45 PM, Adamw said:

Attachment is not showing.  If it is too big you can share a like using google drive or onedrive etc.

 

Adam I got it figured out. I adjusted the arming threshold in trigger 2 at the 1000rpm range to .5 and have not had an issue since.

Pretty happy to have it fire up every time without hesitation. Thank you so much for being here to help answer questions. It finally clicked when I realized what I was looking at on the scope readings. Haven't messed around with an oscilloscope since I was a kid.