E38 Gen 4 Manifold Switch Open vs Closed?

[danmw2003]

I posted this over in the wrong Gen3 subforum, so I will try here. So under my VVE table, there are two different tables for Manifold Switch open and closed. They both show different values. I've been told that copying over the tables so they're the same is what I should do, but that doesnt really answer my question. Does anyone know when the ECM is referencing what table? Open vs closed? I suspect one table (manifold open) is for open loop VE and the other (manifold closed) is closed loop VE. Not sure though. Was hoping could fill me in on what these two tables actually are.

[Boosted C6]

What engine is this on?

[Boosted C6]

Some intake manifolds have a sort of valve i guess you can say in them, if it opens it will run off the open vve table and vise versa. It has nothing to do with open vs closed loop. If you dont have that intake manifold make them the same and keep them the same

[danmw2003]

Its a 2014 Camaro 2SS manual trans LS3

[danmw2003]

It shows a different value over 4000 rpm in the switch closed vs switch open. The LS3 has no valving in the intake.

[Boosted C6]

If the manifold doesn't have that "valve" in it its going to reference the open ve table only. As to why its like that I have no clue

[07GTS]

usually just fill them all with the same values just encase

[danmw2003]

I feel like there's more to it than that, but Im just getting started with my VVE tables and making corrections. I suspect my fueling is different when cold vs when its at normal operating temp. Seems lke it runs considerably lean when cold, but moves toward stoich and maybe a touch rich when at normal operating temperature. I suspect this is the reason for the two different manifold switches, but Im not entirely sure at the moment. Im a bit if a noob and just starting to make VVE corrections.

[village_idiot]

It should be opposite of that. It should run rich when cold, and then lean out to stoich as it warms up. This has nothing to do with the VVE tables, and more to do with the open loop base, and open loop gains tables. Thinking of a stock vehicle/tune, it SHOULD want to run richer than stoich when first started. I always include Air Fuel Ratio Commanded, and Equivalence Ratio Commanded in my scanner channels. Then you can see if it's commanding a 1.00 lambda, 1.15, .85, etc...... or if you use AFR, you can see that as well

[383_Stroker]

Asks for help.... argues with the help...

The "valve" in the intake description is correct. It's also correct that you don't have one.

[RobZL1]

It's also correct to say it has nothing to do with your fueling vs temperature. See also open loop gains, ivt terms, inj tip temp, iat vs ect offset, etc, etc, etc...

[danmw2003]

Not arguing with people here. Im sorry if I come across that way. I'm completely new to this and just trying to better understand what is happening, and what I need to do to make proper corrections. Just trying to understand WHY there are open and closed switch tables that show different values in my stock calibration. Just telling me to make them the same does not answer that question.

[RobZL1]

Understood, but your question has already been answered. As for why there are values there, it's probably because of simulations that populated data there, even though it's not used. Same reason data is there in flex fuel tables in some cars that never had flex fuel, for example. Maybe they just copied an OS and didn't bother with those tables since they weren't referencing them. Either way, you don't HAVE to make them the same. It will still work if you only change the relevant one.

[village_idiot]

The reason it's there, is because GM uses sort of blanket of data points for their PCM's. Same reason that under Engine > Torque Management, you will have Front Axle Max, Front Propshaft Max, Rear Axle Max, Rear Propshaft Max, etc..... and you do not have 4wd. To be overly redundant, and for the slight CHANCE the wrong table ever gets referenced is the "why" to making these useless tables match the ones that are used.

Your car only references Manifold Switched Open

The reason to make Manifold Switched Closed the same, is just doubling down on "what if's"

All of your REAL adjustments that you need to pay attention to, are Manifold Switched Open.... Then just make the other match.... Or don't.

Either way..... VVE is not your problem. As posted by me, and RobZL1.... You need to be looking in the Open Loop fueling tables

[danmw2003]

I guess that makes sense. I suppose I was expecting that the different tables were there for a reason, and that the ECM was referencing them at different times, when certain criteria were met. Never occurred to me that the OEM likely just copy/pasted tables from multiple platforms. Like I said, I'm a noob lol. Sorry for the stupid questions, and thank you for answering them!