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Misfire on opening throttle, vq35de, emu black

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Hi there!

Im helping an friend of mine with an vq35de engine swap in a datsun. As ecu, an emu black is used. i have tuned serveral of these engines thus my involvement. Although i have less experience with ecumaster products.

With the engine running, if i easy get on the throttle to elevate the rpm's i see a very lean spike. This is in mijn opinion a (rich) misfire. I have no reason to doubt the deadtimes but im alway's willing to look at them.

Im also leaning towards swapping out the wideband. Just to be sure.

What would be a course of action on finding out what this lean spike is? and how to fix this :)

I will attach the current map and a log. I am aware that the alternator is not always changing. This is intentional.

Thanks in advance!

Kind regards,


Attached Files

I could be looking at the wrong part of the log but I'm not seeing any acceleration enrichment

Hi thanks for looking.

I see you post changed. there is no enrichment since the tps rate is really low. I was really easy on the throttle.


Attached Files

yeah, I looked over another part of the log and saw the TPS registering. I would start by trying to get the Accel enrich to kick in to see if that helps as it's only a momentary lean spike

Verify fuel pressure. Before you get off in the weeds, always remember you might be dealing with something mechanical or electrical.

I'd disable accel enrich, tune the whole VE table in steady state, then enable accel enrich, then tune accel enrich.

Hello Vincent,

Just had a quick look at your log and your CAM #1 isn't moving, CAM #2 is moving towards target, it's not perfect and might need some PID adjustement but at least it's moving. The CAM #1 DC is maxed at 80% so the system is trying to move the cam but it's not responding, I would check for the solenoid operation.

It's probably not related to your issue as the VVT move after the missfires, but it's still something that needs to be addressed.

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