BOV Killing Motor Gen 2&3 coyote

[zkonmando]

Gen 2&3 Coyotes.

I have been battling some issues on turbo and pro charger cars wanting to shutoff after the BOV opens. This is limited to unlocked converters and is worse when they?re loose/high stall.

I do not believe MAF placement is the issue as this has occurred on a couple of vehicles now. One is my Gen 3 single turbo car and the other is a f1a94 pro charged gen 2 both with loose nonlockup setups.

Is there something to look at to get it catch itself and not die after the bov opens. Normal decel is okay but letting off after boost makes them choke down around 400rpm and maybe they recover maybe they don?t.

Tunes and logs can be added at request. Writing this on the road or I would?ve included them now.

[veeefour]

I have no issues with BO in my tunes/builds

[B E N]

Is your BOV between the MAF and the intake?

[zkonmando]

Is your BOV between the MAF and the intake?

No, bov is before Intercooler, maf is 8ish inches before throttle body if I recall correctly.

[SiriusC1024]

You have to account for the air that's being released. It's already gone through the MAF, so the ECU expects it to still be there. When it's released to atmosphere instead of draw into the engine calcs get thrown off.

[veeefour]

You have to account for the air that's being released. It's already gone through the MAF, so the ECU expects it to still be there. When it's released to atmosphere instead of draw into the engine calcs get thrown off.

But he said BOV is before IC so you do not have to account anything.

[SiriusC1024]

Ah. So much for my reading comprehension.

[zkonmando]

I have no issues with BO in my tunes/builds

Any tips for me to try?

[veeefour]

Post your tune

[SiriusC1024]

And log.

[zkonmando]

R19, maf, dfco.hptw19 2 Step 1.hpl

Good example of the turbo car struggling to idle after getting off the two step. Huge negative fuel trims and down 300rpm versus commanded idle.

[veeefour]

Your problem is in torque model, ~70Nm requested but only ~20Nm expected. Spark tables being the cause.

[zkonmando]

Your problem is in torque model, ~70Nm requested but only ~20Nm expected. Spark tables being the cause.

I?ll look at this when I get back to the house. Thanks for the tip

[zkonmando]

I?ll look at this when I get back to the house. Thanks for the tip

Modified spark tables and removed throttle stop, car will immediately shut off when you let go of pedal.

Gen 3 car TH400
Precision BOV, 7685,
ID1700xdsW24.hptW24 2 step.hpl

[zkonmando]

I am noticing that absolute load is staying highish (60%) after letting go of pedal. Any ideas as to why? Is this related to the issue?

[zkonmando]

Ok, so after hours of just changing stuff. Yes, that was the method, here is the latest tune. If anyone could offer their opinion on why this worked that would be amazing. I know very little about the dashpot multipliers/modifiers but apparently they do stuff that matters as that is what solved this gen 3 car wanting to die on decel. It was actually not only wanting to die after a BOV event but also on free revs (just not all the time which was weird). I have not gotten the chance to drive this tune up yet but it doesn't die off the chip and doesn't die when free revving so hopefully that's good news.

Notes: Covers all the differences between this file and W24 that solved (for now) the issue

Turning idle airmass switch off made it go back into idle corrections faster from what I could tell. Minor positive affects
Normal dashpot mult had minor effect but kept it inline with others
Target N mult had largest changes. Setting to 0 made return to idle much slower/smoother but caused issues with transition to getting back on pedal (think I solved this later)
ADFSO mult seemed to have change when rpm was falling fast or when there was a wide swing in load. Helped transition off of 2 step.

Solution to Target N issue was to 0 out the Launch Airmass Mult. Allowed me to footbrake again and would not close throttle after a rev or on footbrake

Idle feedback enable at 2000 was for it to catch it sooner, definitely helped. Set lower limit to 400 to keep PID system active as a stall saver (may actually be hurting IDK)
Max correction at 100ftlbs as an oh shit save me, same with torque reserve and dash pot rate settings

Torque table changes made it idle in lower spark and more throttle which helped a little but was not the solution, left it this way because it didn't hurt. Still don't have a method that I use everytime on the torque models so gonna try this and go from there

Friction torque was put back closer to stock as it wasn't helping the issue

Wall of 30* was removed from spark tables but did not solve the issue. I could see how this can cause issues with torque calcs and left it gone. Other changes were to help it on the brake and it now it makes 10.5 pounds in under 4 seconds (record for this car)

Cranking fuel is self explanatory

ETC model changes I made by logging ETC error. This will probably be put back to stock at a later date or be continued to be modified based on new data from driving. It is a stock throttle body but I will see what happens down the line or if y'all have suggestions I am all ears

W40.hpt W40.hpl

[zkonmando]

Update

Got to drive it today?

Drives great before a pull and during a pull. After a pull I get dead pedal. Pedal does almost nothing for throttle until 80% APP at which point you get WOT.

Pedal comes back after I let idle circuit take over. Would attach a log but am away from pc at the moment and nothing for torque channels shows anything happening outside the norm.

Any advice? Will update with new tune and log soon.

[zkonmando]

W45.2.hpl W45.hpt

Latest tune and log. You can see the dead pedal thing a little before the green marker in the datalog.

[zkonmando]

Solved the dead pedal issue by disabling desired airmass logic all together. However, now the issue of dying after the 2 step is back. Any ideas? Latest tune and log attached

W54.hplW54.hpt

[zkonmando]

If anyone is willing to teach me how to fix this I am more than willing to pay for their time and knowledge. I do not want someone to tune the car, I want to learn how to work through these problems.