Low Timing At Idle & RevMatch / LT1 / Novi1500

[DorkMissile]

So I have been going around and around with this with my tuner for some time now - and want to see if we can get this smoothed out

What I have been chasing is that I get into a scenario where during gear changes (car is a 6th Gen Camaro 1LE) upon letting the clutch out during partial throttle cruising / driving that there is hesitation when tipping in the gas. At times it is almost completely gone, and at others it is just noticeable - until you try using the RevMatch feature and then it is very pronounced. You can roll into the gas and it is a second to maybe a second and a half where it is a dead throttle pedal. Problem is the car has a Paxton on it, when it comes off of the dead pedal situation, you can jump right into a decent amount of boost.

That being said - doing some logging today - I think I actually found something unique going on. FYI - prior to this I did a "Throttle Body Cleaned" relearn using the tools in the scanner.

In this log - the first 2m30s is driving around without rev match on. I don't feel anything peculiar here other than the timing is very low when reading down to .08-.12g of airmass, where it is outputting 0-7degrees of timing. And at times it will idle at 0 deg of timing. After 2m30s, I am driving the same route, with RevMatch on, and it seems to have more timing, but the hesitation comes in right when in the log under "Immediate Engine Torque Source and Predicted Engine Torque Source" it has a value of "Unkown". I cannot get these values at any point while logging with RevMatch off.

I am presuming the tune is referencing a table that is missing?

Pardon my lack of experience - i paid to have the car tuned and have had this very issue amongst two different engine configurations, but I am trying to be resourceful on how to get the "dead pedal" resolved and determine why the timing is so low at idle.

Current build:
LT1 / Stock Crank / K1 Rods / Wiseco 10.5:1 Pistons
BTR Stg2 Cam / Locked 0deg cam timing / Johnson Lifters
Stock Heads / BTR Springs / E85 Sensor / ECS Novi 1500 / 13lbs Boost / 2" Long Tubes with Cat deletes / Alky Meth with (1) 15# nozzle

[ZincGT]

Do you have a baro break out? looking at your log it never changes p ratio. Your VVE table is also very odd (at least to me it is)

EDIT: Appears that you are not logging barometric pressure thats why your P ratio is not functioning correctly. Add that to your channels list, put the car in open loop and use your wideband to tune both VVE and MAF.

[DorkMissile]

Do you have a baro break out? looking at your log it never changes p ratio. Your VVE table is also very odd (at least to me it is)

EDIT: Appears that you are not logging barometric pressure thats why your P ratio is not functioning correctly. Add that to your channels list, put the car in open loop and use your wideband to tune both VVE and MAF.

Car does have a Baro Harness on it, and IAT sensor in the intake directly behind the TB

[DorkMissile]

And BTW thank you ZincGT - I have yet to tackle my own tune so I am at a crossroads to live with it how it is, take some classes and learn on my own or find a new tuner. Trying to talk with the current tuner is a challenge as he is busy (has another business).

As far as the Channels & PIDs, I am just logging what he gave me. I can add everything, but am concerned about my own edits (I own my credits - have access to everything in the tune if needed)

[cmitchell17]

I have experienced the exact same thing that you are describing about the hesitation at tip in throttle. My guess is it is either the air flow model (maf and VVE) being off enough, if you are in open loop. Or it is the timing being extra retarded in that area. I used to think it was because the PCM was stuck in engine torque source "idle" and had not transitioned to "axel" yet, but in the logs I can see the torque source change almost instantly whenever accelerator position becomes non zero.

As for the torque source "unknown" I have had this exact same problem and usually its something requesting a torque reduction so it comes in and pulls the throttle or timing back.