Boosted 2016: ETC Closing, But no Limits...

[CCS86]

I understand mechanically what the blower is doing. But the throttle calculation for all intents and purposes does not understand there is a blower attached, you've worked around that somehow.

Something about the internal logic of this strategy is challenging your conception of how it all works, so the solution is probably something you might object to on merit alone.

I would definitely raise desired load and/or modify your TTL to rule it out. Air load is close to/slightly above desired, EBT is reasonably below ETC Request. Depending on your distance from MBT, that's an odd situation for the PCM to rationalize.

Correct. A big part of getting boosted (especially PD) cars to drive well is adapting the NA strategy to work with the massive ramp in VE as the bypass shuts. I have tuned maybe 20 PD blower Coyotes and have never seen this behavior. Even when the TB model is way off, WOT START/END points should force the TB open.

You are also saying "raise the desired load". Can you be more specific about what you are suggesting? I would assume you are talking about TQ/INV tables, but hate to assume.

[RobCat030]

Torque tables is probably a good place to do it. It's hard to suggest changes without seeing the tune but I fully understand why you don't want to share. I mostly deal with turbo stuff on NA Tricore PCMs vs blowers, but the point where the turbo starts spooling is *sort of* similar to the bypass closing. I used to make a ton of throttle body data changes, these days I use the torque tables and put a huge gap between Torque and Inverse tables. Neither are ideal but at a certain point you gotta get the customer out the door. Can't make every car a science project.

Desired load is, loosely, a conversion of driver demand -> torque inverse tables. Then you use engine displacement to get a desired MAF value (you know all this, I'm just reiterating). In my general experience, both desired torque and load vs actual are used to adjust the throttle, but only torque is used for the IPC check. This is why the throttle can close without any IPC error. But that's not universal across all years and platforms.

I empathize with the frustration about logic changes. To me, it's a reminder that our understanding of this stuff is 30-50% *at best* until the day where all the information is on the table. My solution is to have a go-to strategy for every MY year, and I push that strategy to the car before I read it with HP. It saves a TON of headaches.

[rstoco]

This looks like my friends car when he went from 3.31 to 3.73 with out updating the tune for it.

Simple update, the BCM didn't learn it or atleast not very quickly or after a few miles of driving.

Attachment 126957

you have email to contact?

[geddys]

Even when the TB model is way off, WOT START/END points should force the TB open.

On friends NA car we had issue that it would close TB on high rpm on 1st gear only @ WOT, and better TB model fixed this issue completely. I would suggest lowering TB effective area and try if anything changes.

[CCS86]

Torque tables is probably a good place to do it. It's hard to suggest changes without seeing the tune but I fully understand why you don't want to share. I mostly deal with turbo stuff on NA Tricore PCMs vs blowers, but the point where the turbo starts spooling is *sort of* similar to the bypass closing. I used to make a ton of throttle body data changes, these days I use the torque tables and put a huge gap between Torque and Inverse tables. Neither are ideal but at a certain point you gotta get the customer out the door. Can't make every car a science project.

Desired load is, loosely, a conversion of driver demand -> torque inverse tables. Then you use engine displacement to get a desired MAF value (you know all this, I'm just reiterating). In my general experience, both desired torque and load vs actual are used to adjust the throttle, but only torque is used for the IPC check. This is why the throttle can close without any IPC error. But that's not universal across all years and platforms.

I empathize with the frustration about logic changes. To me, it's a reminder that our understanding of this stuff is 30-50% *at best* until the day where all the information is on the table. My solution is to have a go-to strategy for every MY year, and I push that strategy to the car before I read it with HP. It saves a TON of headaches.

I appreciate the reply.

I would agree that the inverse table is doing the real conversion from torque request to desired load, and that the TQ tables are more for error checking and they don't have to match.

What device are you using for the initial strategy swap?

I really wish we could look deeper into the underpinnings of the strategies. Being able to change table dimensions, see and change references connecting tables / inputs / outputs would be so cool.

[RobCat030]

FORScan works with pretty much any J2534 Passthru device, there's a beta version of it that can flash factory VBF files. The Tactrix Openport 2.0 is probably still the cheapest on the market at ~$160. There are fakes out there so be careful not buying direct. You'll see a bunch of Subaru-related stuff but these are Ford compatible. You can mail these out with a safety deposit from the customer for remote tuning. This might not be an endorsed method but in my view it's fair as long as the credits are paid.

I really wish we could look deeper into the underpinnings of the strategies. Being able to change table dimensions, see and change references connecting tables / inputs / outputs would be so cool.

I agree. At the very least it'd be nice to have a community-oriented database of "no-go" strategies. I think a lot of the threads on here that go in circles with anecdotal back-and-forth is mostly caused by this. I'll PM you with some more info

[veeefour]

Torque tables is probably a good place to do it. It's hard to suggest changes without seeing the tune but I fully understand why you don't want to share. I mostly deal with turbo stuff on NA Tricore PCMs vs blowers, but the point where the turbo starts spooling is *sort of* similar to the bypass closing. I used to make a ton of throttle body data changes, these days I use the torque tables and put a huge gap between Torque and Inverse tables. Neither are ideal but at a certain point you gotta get the customer out the door. Can't make every car a science project.

Desired load is, loosely, a conversion of driver demand -> torque inverse tables. Then you use engine displacement to get a desired MAF value (you know all this, I'm just reiterating). In my general experience, both desired torque and load vs actual are used to adjust the throttle, but only torque is used for the IPC check. This is why the throttle can close without any IPC error. But that's not universal across all years and platforms.

I empathize with the frustration about logic changes. To me, it's a reminder that our understanding of this stuff is 30-50% *at best* until the day where all the information is on the table. My solution is to have a go-to strategy for every MY year, and I push that strategy to the car before I read it with HP. It saves a TON of headaches.

Here is the latest boosted tune i did...nothing is closing...as desired is higher compared to actual air load...
If you take a closer look you can see desired follows MAF curve, I know it falls dawn later but that was TC kicking in.
Low boost max 7 psi and yes, it does not matter it's a supercharger or turbocharger.

cheers for having a good understanding about this problem...you might try to educate people should you want to take the hassle.

desired-load.jpg

[CCS86]

Here is the latest boosted tune i did...nothing is closing...as desired is higher compared to actual air load...
If you take a closer look you can see desired follows MAF curve, I know it falls dawn later but that was TC kicking in.
Low boost max 7 psi and yes, it does not matter it's a supercharger or turbocharger.

cheers for having a good understanding about this problem...you might try to educate people should you want to take the hassle.

desired-load.jpg

Can you post a picture showing a slow, smooth pedal roll on to WOT?

[CCS86]

Here is the latest boosted tune i did...nothing is closing...as desired is higher compared to actual air load...
If you take a closer look you can see desired follows MAF curve, I know it falls dawn later but that was TC kicking in.
Low boost max 7 psi and yes, it does not matter it's a supercharger or turbocharger.

cheers for having a good understanding about this problem...you might try to educate people should you want to take the hassle.

desired-load.jpg

Doesn't look like TC kicking in to me. Spark and ETC angle stay constant at the point that desired load plummets and air load stays high.

[Plimmer]

So I'm having the same but opposite problem to you with my car, the throttle opens more than the pedal is suggesting, and I see veeefour also has this problem, see highlighted area in his log:


I'm going to start a separate thread for my issue, but basically we are all experiencing pedal and throttle not working together, but can't figure out why.

[Plimmer]

Here is the latest boosted tune i did...nothing is closing...as desired is higher compared to actual air load...
If you take a closer look you can see desired follows MAF curve, I know it falls dawn later but that was TC kicking in.
Low boost max 7 psi and yes, it does not matter it's a supercharger or turbocharger.

cheers for having a good understanding about this problem...you might try to educate people should you want to take the hassle.

desired-load.jpg

So I'm having the same issue as you, the throttle opens more than the pedal is requesting, but chasing my tail trying to solve it.

I'm going to start a new thread with my log and tune, but I can't figure it out. Here is what my pedal vs throttle looks like:
Screen Shot 2023-01-22 at 6.39.47 PM.png

[engineermike]

Ccs86 was this ever resolved?