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2jz vvti rpm issues

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I have a 2jzgte vvti, running on an aem infinity 8h. My issue is I can’t get it to rev past 6000rpm with boost. Basically feels like I’m hitting a rev limiter. I’ve sent data logs to aem. And all they can say is use my noise canceling. But when I use it it get worse. It’s very consistent at 6000rpm. Never goes past. I’m hoping someone my have seen this before..? I’ve checked wiring and connections. Basically everything I can think of. Any suggestions would be great. Thanks

Found this on the AEM forum that may be of use.

"Here's how I'd troubleshoot this. First, load the semi-sequential firmware - you'll need to download it from Be sure to save your cal before hand because you'll want to import it in once your on the semi-seq firmware. In the Cam/Crank wizard, uncheck Sequential Enable - this will make the Infinity run in semi-sequential mode with two injection events and two ignition events (waste spark) per cycle. In order to correctly run in semi-seq, you must physically unplug the cam sensor from the engine. The engine should start and run like normal now. While you're doing this testing, I suggest turning your boost target down to waste spring. I wouldn't keep pushing the engine hard with high boost until you get this sorted out.

The point in running semi-seq is that you're running on just the crank sensor so any issues that come up must be limited to just the crank. You'll want to adjust the Noise Cancellation values in order to get the engine to run clean to your desired RPM without having Sync or Timing Errors occur. Once everything is dialed in and working correctly on just the crank, go back to sequential mode by checking Sequential Enable and reconnecting your cam sensor. Now, any errors that occur after adding the cam back in must be due to the cam since everything was good with just the crank. Now you can troubleshoot the cam specifically and get everything dialed in.

FWIW, a lot of digital crank inputs with high tooth count trigger wheels sometimes needs Noise Cancellation values less than 10. We find that VR sensor typically need higher NC values whereas digital sensors often need less. I also suggest only having Sync Response when Sync Error Crank Tooth Missed/Present set to Re-Sync - all other settings should be Ignore for now. These settings live in the Diagnostic part of the wizard"

Thanks Rob for this information. I’ve never done that before so I’ll give it a try. I am on oem sensors. And I’m starting on 10 for my cancellation and it doesn’t change until I get to about 60. Then rpm starts to drop to 4500. Could my timing be an issue? Or anything else you may suggest is welcome.

Thanks again

Are you getting any timing errors when you're logging that channel? at 6000rpm if its starting to report errors...etc I would suspect it might be something like a noise issue..etc. Try to narrow it down as best you can to one sensor using the method above. Unfortunately diagnosing things over the internet can be difficult as there are so many variables.

I suspect timing issues would show itself in a different fashion, but checking base timing is easy enough with a timing line. Just set the infinity to hold whatever degree you can reference on the timing cover and make sure it doesn't wander when revved up.

Let me know if you get any closer to resolving it. It is always good to know what the problem ends up being.

Thanks again Rob will do.