86's behavior(tuning pov)

[SteveIsBored]

What are your IATs when all of this is happening? You could have knock correction plus high IAT correction, this could all be causing high egts. My knowledge is limited but I was logging similar performance issues when running crap 91 with high IATs

[ztan]

Originally Posted by yomny

I noticed the yoyo timing.. I have a log I did today and I get correction up to -3 and then addition, not back to back but fairly close in the event. I'll see if I could post some logs or something to show what im trying to explain as my tuning vocabulary is very limited. I didn't understand the part about load limits.


What puzzles me is that is not constant or always, just at times. That's why I initially thought it was a temperature thing.


Your help is very appreciated.

Timing map is suspect if you're pulling 3 degrees under load.

Also, what port injectors are you running and how have they been balanced with the DI system? When I switched injectors, it took me a while to sort out the areas where the PI system turned on, but operated in a non-linear range - have you logged PI and DI pulses and to see if the hesitation occurs with switchover?

[yomny]

Originally Posted by ztan

Timing map is suspect if you're pulling 3 degrees under load.

Also, what port injectors are you running and how have they been balanced with the DI system? When I switched injectors, it took me a while to sort out the areas where the PI system turned on, but operated in a non-linear range - have you logged PI and DI pulses and to see if the hesitation occurs with switchover?

Im running stock fuel system for now, seems to be ok for 10psi of 93 oct. Never really logged the PI and DI pulses.

[yomny]

Originally Posted by SteveIsBored

What are your IATs when all of this is happening? You could have knock correction plus high IAT correction, this could all be causing high egts. My knowledge is limited but I was logging similar performance issues when running crap 91 with high IATs

My IAT were 98F max, low 93F it must have been around 90F outside and i dont have any source of cold intake.

[yomny]

Trying to attach a few logs I've taken.. see if anyone could check out. These are all city drives with the "morning" one having a lot of idle time as i sat in traffic and the rest have some mild throttle applied.

[steve99]

Originally Posted by yomny

I noticed the yoyo timing.. I have a log I did today and I get correction up to -3 and then addition, not back to back but fairly close in the event. I'll see if I could post some logs or something to show what im trying to explain as my tuning vocabulary is very limited. I didn't understand the part about load limits.


What puzzles me is that is not constant or always, just at times. That's why I initially thought it was a temperature thing.


Your help is very appreciated.

load limit tables look like this

[cjd]

Just to be sure, this happens with A/C off? Maybe you said and I missed it...

Stock, A/C definitely sucks away power.

[ztan]

Originally Posted by yomny

Im running stock fuel system for now, seems to be ok for 10psi of 93 oct. Never really logged the PI and DI pulses.

You've got DI and PI pulses on the log - if you're stock, you shouldn't have too many transitional issues.

Your logged IAM = 0.2!! and still has (-ve) corrections. You'll need a better tune or fuel. With that IAM value, you'll be running much more of the Base timing table A (as defined in RomRaider) than Base Timing B (which is what most of the tuners adjust as it affects timing when IAM = 1.0).

[steve99]

Originally Posted by ztan

You've got DI and PI pulses on the log - if you're stock, you shouldn't have too many transitional issues.

Your logged IAM = 0.2!! and still has (-ve) corrections. You'll need a better tune or fuel. With that IAM value, you'll be running much more of the Base timing table A (as defined in RomRaider) than Base Timing B (which is what most of the tuners adjust as it affects timing when IAM = 1.0).

yep just saw that iam looks pretty ordinary if he is running correct fuel for tune.

side issue do you know the parameters the ecu uses to determine the base timing b to a switching or transition.

i know it runs base b plus knock correction max a when iam is 1

so at what point does the transition occurr to base a plus i assume knock correction max a to determine overall base timing plus offsets due temp iat ect ?

[ztan]

Originally Posted by steve99

side issue do you know the parameters the ecu uses to determine the base timing b to a switching or transition.

i know it runs base b plus knock correction max a when iam is 1

Grossly, what I recall from looking at the disassembly, the IAM acts as an interpolation value between tables B and A:

Base timing = IAM*(Base timing B) + (1-IAM)*(Base Timing A)

IAM*KCA is added to this and then corrections are made to get a final timing value

***
Ignore above...

I was thinking of Primary OL fuel table which progressively adds in fuel from the OL additive table based on IAM.

Just had a look at the dissassembly again and Base Timing tables do not have an obvious IAM modification. The Base Timing A and B tables in A01G are interpolated based on a value stored at FFF8ADB8 - this logs at 1.0 during normal operation (full Base_Timing_B map), and 0.0 (full Base_Timing_A) at startup and shutdown.

[VitViper]

Originally Posted by yomny

Trying to attach a few logs I've taken.. see if anyone could check out. These are all city drives with the "morning" one having a lot of idle time as i sat in traffic and the rest have some mild throttle applied.

Was this done on a dyno? From those logs and how super low the timing is, one can make the assumption you're either running 87 octane fuel or there's something in your engine bay making a ton of racket and making the knock sensor go crazy. The timing map is in various spots makes one wonder. The IAM being super low is a result of the knock sensor feedback -- although it may not mean much as you can tune the timing maps to shift very little if none at all due to the IAM.

You're also seeing stoich AFR's while making boost, and you really should be seeing some enrichment when boost comes in -- the leaner AFR in boost will cause cylinder temps to shoot up which can cause some detonation.

[s2d4]

Considering you have wideband, why aren't you running full closed loop?
Enrichment on throttle as well as boost should be there as mentioned.

I will not be loading your car at all with IAM that low, putt around and make sure you have fuel side sorted by getting better fuel to eliminate it from the equation. If it's still happening, you need to get your tuner to do something.

[Kodename47]

Originally Posted by steve99

at what point does the transition occur to base a

Base A is when the AVCS isn't operational, so when the car is in it's warmup phase

If it's ECUtek, could there be an issue with the hybrid SD? This would be impossible to determine by logs alone though as you would need to see how it's setup.

FWIW, I haven't looked at the logs as it seems you have that covered above.

[steve99]

Originally Posted by Kodename47

Base A is when the AVCS isn't operational, so when the car is in it's warmup phase

If it's ECUtek, could there be an issue with the hybrid SD? This would be impossible to determine by logs alone though as you would need to see how it's setup.

FWIW, I haven't looked at the logs as it seems you have that covered above.

here is an easier to read log from yommy

http://datazap.me/u/steve99/log-1440...-35-39&solo=33



side issue :-)
so your saying base timing A only get used at startup or limp mode and never used after that, ie their is no interpolation from B to A when IAM drops