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Changes to Link VE table not affecting lambda readings

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Looking for some help with a cause as to why changing VE has no affect to the recorded lambda reading on a Link G4+ PNP for a BMW M50. Entered the injector data, fuel pressure, and engine capacity to what should be correct. The lambda at idle seems to be steady at 0.78 no matter the changes I make to the tune.

Things I have tried:

Changing VE table values

Changing base fuel pressure settings

Changing to a traditional fuel method

All with no change to lambda. One thing I noticed is the Injector duty is at 2.5% at idle. Is this a normal occurrence while running rich at idle?

Attached is a copy of the pclr file in case anyone would like to take a look.

Engine is an bored M52 bottom end with a M50 head, S366, 1200cc Southbay injectors running on E85.

Lambda reading is coming from a brand new AEM X series wired to the Link

Any advice would be greatly appreciated

Attached Files

Have you verified that the wideband is working/on the right channel? If you make huge changes to the VE table does it swing to very rich or lean and want to stall?

On a side note, your idle ignition table is usually set up with the X axis as Idle Target Error so it will ad or subtract timing based on your Idle Target RPM Table and would look more like the table below with the numbers in the columns appropriate for your situation. Hope that helps

Attached Files

That map you attached doesnt appear to be the one you were using. The ECU statistics shows zero engine starts and a max rpm of zero. Theres a few odd things such as your MAP is showing 185Kpa with the engine off.

You have a minimum effective pulsewidth of 1.1ms set, are you sure you are not hitting that?

Can you do a short PC log of the engine running and attach the actual map that was used to run the engine.

Adam, attached is a short log of idle and the actual tune file off the car.

Rob, thanks for the idle ignition table advice, I will try that out.

The lambda value off the gauge and what is being displayed in the Link Software is exactly the same. If I throw fuel at it, I can hear the engine want to die but almost no change to lambda

Attached Files

No worries Tucker. Your Idle Ignition Control is inactive due to your rpm lockout being below the actual rpm which is 250rpm above target.

I can't help you with your fueling issue at this stage but if you need a hand getting your idle targets sorted once you have the fueling in hand just sing out mate.

Thanks, will do!

For anyone else that takes a look. I noticed the iat sensor wasn't configured. After configuring and driving down the road I'm able to keep the lambda in check. It's just idle and light cruising area I can't get the fuel under control.

As I mentioned in my first post, you are hitting the minimum effective pulsewidth that you have set once your VE number goes below about 50%. I suspect your deadtimes are wrong judging by the shape of the deadtime curve but the quick fix will just be to reduce the minimum PW setting.

Hey there Tucker, I do not know if you have figured this out or even our situations are related but I am having the same problem to say the least. My car is a 1999 BMW 328iS (e36) with the M52 engine and an M50 Manifold swap. I was on my way to scaling the MAF with the stock ECU using the Innovate Motorsports LM-2 as my data logger and wide band lambda meter. The tools I have are the Alientech Kess V2 and the ECM Titanium. When going for a test drive, I have set the WOT lambda to .80 but no matter what I do there is no change. Lambda readings are always the same and what happens is the LM-2 just keeps reading richer and richer all the way down to .77 during a WOT ramp run. The car seems to do what it wants and gets most rich after around 4200 RPM where VANOS kicks in. When doing an increasing RPM test where I gradually accelerate up to VANOS territory, the lambda stays around 1 even as pass the VANOS RPM. I would expect that to become more rich and not stay the same throughout the whole run. I wish I had an idea as to what is happening.

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