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GR8GAME
October 21st, 2018, 06:21 AM
E92 Cadillac Escalade.

Customer installed a camshaft into the truck. Lowered the compression ratio.
I'm having issues where the idle is "hunting" a lot. You can see it pulling timing and then the TB will "jump" up to try to keep it from dying. It makes it difficult to drive. I'd like to get it solved and understand a bit more about these controllers idle strategy.

I've tried several things with no luck. I was hoping someone may know where I need to make adjustments.

So, here is what I've tried and the way I understand what's going on....
B1823: This is the MAX the throttle can move to adjust for idle irregularities

B1821: Self Explanatory
B1874: Deadband...what I "assume" is going on here is that if you set this to a certain RPM, it will be the "same" as setting B1861 in those same areas to all zero's...???
B1875: Same above but with regards to B1862

B1863: How much the PID controller makes adjustments

B1864: I'm not quite sure, have a theory though

B1865: Same as above. I would like a better explanation on these two tables if at all possible.

B1879, B1880: I'm not sure what this pertains too. I've tried to see if they made a difference...and they didn't for my applicatoin

B1870 - 1872: I'd like to know what this does.

I'm not seeing any "idle airflow" style tables, so I'm assuming the PID controller is very TQ based like the rest of the ECU strategy.

Another thing I may be fighting is timing.
So, in the DVT controls of the Scanner, I can't control anything???
Is there an update? I can't control timing to see what the motor likes. So that's a bit of an issue.
I'm not dealing with a stock vehicle or a stock file, so I know that's a handicap as well.

I also want to note:
The tune file I posted is from someone else. It's a bit of a shitshow. I turned the High Speed air back ON. I then tuned the VVE to within +/- 5% of my commanded fueling. So, with the file posted, it doesn't have this issue. It is steady BUT, the fuel trims are so far out of whack, it is -20% on the fuel trims. So yeah, I can't trust it. But I'm also wondering if by turning off the VE, it shuts off some of the idle tables?

OPEN LOOP:
I can't seem to command the processor into a constant open loop. Does someone know how to do this?
I have found the table in another software and I can't find it in EFIL. I know that's always the way I've tuned in the past. I'd like to tune this processor that way too.

Also part of Open Loop:
B0142: EFI shows this table as being "cold". I'm assuming this is a startup thing. So, does this table have ANY effect on WOT when in Open Loop?
I ask this because with the other software, it doesn't state anything about a cold start up and I've read that it seems to effect ALL open loop situations (Or I'm reading it wrong, LOL) I would like some clarification on that too, please.

Thank you for any help or input.


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joecar
October 22nd, 2018, 01:21 PM
I'm looking at your log, I'm trying to see if I can understand what is going on.