Hondata

My K24 is running rich and cutting out when VTC hits, which seems like it would be a failing vtec solenoid, but the log values look OK. Are those log values actual results, or target numbers?

Without seeing the calibration and datalog it is hard to say.

Calibration and log attached. It is running rich, even at idle. I think this is due to a new fuel pump. AFR was good at low RPMs with this calibration, but then I replaced with an aftermarket one and am seeing rich across the board.
Thanks!

CAM and CAMCMD appear to be following each other and I do not see what you have described. Have you discussed this issue with your tuner?

Trying to get in touch with a tuner to diagnose. Seriously- the tuner had a stroke, and I'm trying to get someone else at the shop to take a look.

The issue is, the car won't rev past around 5k rpm under load. It stutters and and the rpm's don't increase. It also appears to run rich at that point.

I'm looking at the log, and it looks like around 21 seconds is when it craps out. The engine feels like it's hitting a governor and won't rev higher.

That is when VTEC engages, not VTC. If your VTEC solenoid is not activating that could explain why it is not revving. You could also have a groudn issue and the ECU is grounding through the VTEC solenoid.

Thanks- that's helpful. I was assuming they were the same.

I will take a look.

I've checked wiring from ECU to solenoid (continuity and ground are good), and also checked the solenoid on and off the car. Everything seems fine. I can see in the datalog that the ECU says VTEC is firing, but the car definitely cuts out when it should engage. I've also moved the VTEC engagement limits to double-check.

I've already replaced the spool valve solenoid screen and changed oil/filter. Oil is topped off.

I'm thinking of running a test-lamp to the solenoid leads to see if it's actually getting voltage. Anything else I should be checking?

Have you checked the grounds in the engine bay?