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AFR Gremlin


ManwithSupra

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attachment.php?attachmentid=229628&stc=1&d=1540057365

 

 

In the graph above it shows that the Closed loop system is active, regulating the lambba around 0.90. The final value sent to injectors in this area is around 2.3/2.4.

 

Then for some reason the closed loop system becomes disabled, and the signal to injectors increases to 2.9/3.0, and your lambda drops to 0.72.

 

You can also see a small blip where the closed loop fuel system kicks back in, and the lambda raises, before being disabled again and lambda drops again.

 

Without seeing map config file, it's hard to say what the condition for closed loop system are. But if you can figure out why closed loop is being disabled and re-enabled, then might lead in the right direction.

 

If this lambda sensor is to be believed, then it looks like the rich condition is being induced from ECU rather than hardware.

fuel.png

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Here's also a good one.

 

When routing around after checking the Fuel pressure reguator for signs of leaks in the diaphram I noticed this odd noise coming from the Injector area...

The Ignition is on but engine is not running as I am datalogging from the Syvecs ECU ... sounds like an injector is firing by itself, if its not an injector what the hell could it be and could it be releated...

 

https://www.youtube.com/watch?v=PiZIMGGVblg

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if that's happening all the time you could pull each injector plug off one at a time to find what injector / if its a injector. failing that get a long screw driver and put it on the injectors and listen to the handle touching your ear, could be a earth fault with that injector wiring as im pretty sure they have voltage and are earthed to trigger so a wire touching a body panel could cause that.

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Just looked through the config file and went through log again. I'm not a syvecs wizard by any means, but I couldn't spot anything in relation to cold start, closed loop fuel control or fuel corrections that looked out of place. Comparing the logic of settings versus what's being shown on the log, it seems that most systems are reacting as they should.

 

With the variables available in the log I cannot find anything that is instigating an increase of fuel either.

 

Throughout the log there are sporadic moments where it gets rich. At which point the closed loop fuel control turns off as the lambda readings goes beyond the control limit for the CLL system. Once the lamda sorts itself out moments later then all other system resumes as they should.

 

Also interesting to note that the closed loop system, whilst enabled is constantly trying to remove fuel, but seems like the requested amount of fuel to be removed is not being reached.

 

attachment.php?attachmentid=229639&stc=1&d=1540329282

 

 

Here you can see the random increases in lambda. I think this may be a hardware related issue.

random spikes.png

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Just looked through the config file and went through log again. I'm not a syvecs wizard by any means, but I couldn't spot anything in relation to cold start, closed loop fuel control or fuel corrections that looked out of place. Comparing the logic of settings versus what's being shown on the log, it seems that most systems are reacting as they should.

 

With the variables available in the log I cannot find anything that is instigating an increase of fuel either.

 

Throughout the log there are sporadic moments where it gets rich. At which point the closed loop fuel control turns off as the lambda readings goes beyond the control limit for the CLL system. Once the lamda sorts itself out moments later then all other system resumes as they should.

 

Also interesting to note that the closed loop system, whilst enabled is constantly trying to remove fuel, but seems like the requested amount of fuel to be removed is not being reached.

 

http://www.mkivsupra.net/vbb/attachment.php?attachmentid=229639&stc=1&d=1540329282

 

 

Here you can see the random increases in lambda. I think this may be a hardware related issue.

 

Cheers for looking into it mate, I too keep drawing blanks.

Its clear that there must be something physcial causing the issue rather than the software as like you said its pulling fuel right from the start and the condition gets so bad once the injector duty cycle increases as it warms up it cant adjust any longer and shuts down the CLL.

 

Either it has to be a bad FPR or a stuck injector... it has to be something hardware related.

I was looking at the FPR and it does seem to work, at being just shy of 38psi when idle and around 44 psi on WOT. There is no fuel in the vac line which means the diaphram is in tact at least.

I am placing my bets now on a faulty injector, ether stuck open or it firing randomy due to a short.

 

The thing is I dont want to adjust the fueling until I test everything out as it will just be masking the issue and worse still maybe making 5 of the cylinders run dangerously lean.

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