experts, can you please take a look at my first cam logs

[joshz06]

What year is the car (can't open the file here)

The older OSs had less aggressive spark correction. With a cam, you can run (need to run) more timing in low load/RPM due the the natural inefficiencies of a bigger cam.

its a 2001 Z06, and i basically looked at 12secss's tune file for his fm13 and copied the timing tables, minus 2 degrees all over. i am sure i can use more timing in other places. not to mention, hes got an lq9 or lq4, and ive got an ls6. so i was just really ball parking it. adding timing makes me nervous.

shortly after 6, i should have a new log file and tune posted up to reflect the changes i have made. stfts are more balanced out, and afr is not that far off unless i let off the gas and decel.

i have to be honest, i like DFCO. it engine brakes much harder with it enabled then without. i think i might turn it back on.

[joshz06]

ok, here is a drive scan from my way home from work. now, the stft's are all jacked up at first because i forgot to reset. i reset them on the highway, you can clearly see where. however, now they are all mostly negative... but i am still "lean" according to my wideband?

i am going to attempt to nail down open loop only tonight at least at idle via RTT... do i need to tune the VE tables, or the MAF tables, and which first? i know i will need both. any other things i should look at?

[joshz06]

ok, i turned closed loop off on the highway, and dialed in the ve table. boy it was way off. anyways, i have it running "ok" in open loop only. its not perfect, but it really needs a dyno so i can hit every cell. maf is more dialed in now too, it runs ok. however, i am getting a HORRIBLE dropping idle when i clutch in.

PLEASE, can someone take a look and advise me on how to get rid of it. it used to only do it once in a while, now it does it no matter when i push the clutch in. its very very annoying.

[WS6FirebirdTA00]

get an idle log of it and then a log of the dip. Log throttle cracker and follower airflow as well. You can delete the IAC, MAF g/sec, desired idle airflow, idle base gear airflow, FTC, and ETC desired pid from there as well.

[joshz06]

get an idle log of it and then a log of the dip. Log throttle cracker and follower airflow as well. You can delete the IAC, MAF g/sec, desired idle airflow, idle base gear airflow, FTC, and ETC desired pid from there as well.

ok, will report back later today. thanks for the tips

[joshz06]

throttle cracker is 0... disabled. follower airflow is also 0 for the entire time i scanned. its not that. it is doing it more often then not too.

[WS6FirebirdTA00]

did you do a cold start up log with the idle air trims?

[joshz06]

did you do a cold start up log with the idle air trims?

yes, i used russ k's idle config and copied those values into my raf table. i can do it again if needed, or i can post those logs when i get home.


also, i can not get the readiness tests to come up in the DTC window... how do i get those ready to pass an emissions test.

[joshz06]

just wanted to give an update... i think i have fixed my clutch in rpm dipping issues. when i would be rolling and clutch in, rpms would drop to 450-700. my commanded idle is 875. anyways, the VE table was dipping down into the 95-100 kpa range and my VE table was set to like 57 and 59 and so on... stock values. i only changed up to 85kpa. so i dropped those by a ton down to 48, and it still does it but only about 100 rpms now. so i lowered them 3 more points and ill try out when the car is cold next time.

now, actually, the idle sometimes hangs right around 1000rpms... which i do not have a problem with. should i re enable the throttle cracker now since i have this issue fixed?

[joshz06]

also, if you are dialing in your MAF table, what would be the best guesstimate or however you want to say it, at how much in AFR does changing the maf table by say like 1 full gram equal...

like say i change a value in a cell thats 150.0 grams of airflow and the air fuel is say 12.7. i am commanding say 13.0. the maf error histogram is telling me 2% error... im not buying it. would you say that removing like .8 grams would get me the .2% of AFR i need?

can you even estimate like that?

[Russ K]

Actual AFR/commanded AFR=AFR error %. 12.7/13.0=.98. So the histogram is right at -2% error.

Russ Kemp

[joshz06]

Actual AFR/commanded AFR=AFR error %. 12.7/13.0=.98. So the histogram is right at -2% error.

Russ Kemp

but if i change the values by 2% to take away 2% of the maf value, it ends up being too lean. would it be safe to say the VE table is off at that point? im not even going to try to dial in the VE, its a pain in the butt and i am a maf guy all the way, i HATE speed density. i have the ve tuned fairly well, i did an open loop speed density tune on it the other day( yeah i know i said i dont like it, but it needed it) and that is also an average... it does not represent that sometimes that number could be 15% error, and then sometimes it could be 1% error. im confused now.

[5_Liter_Eater]

VE and MAF are totally independent. You're only using one or the other to meter the airflow at any given time. Once you start getting within 2% you need to start multiplying by half to avoid overshooting...Are you using a wide band?

[WS6FirebirdTA00]

Under 4k RPM it is a mix of VE/MAF. You need to do the VE table if you want to do it right.

[5_Liter_Eater]

Or, if you're so opposed to SD/VE, you can change the dynamic airflow high RPM disable field to an RPM less than idle. This essentially disables the VE table(s) and only uses the MAF for air metering.

[joshz06]

VE and MAF are totally independent. You're only using one or the other to meter the airflow at any given time. Once you start getting within 2% you need to start multiplying by half to avoid overshooting...Are you using a wide band?

yes, i am using a plx wideband.

[joshz06]

Under 4k RPM it is a mix of VE/MAF. You need to do the VE table if you want to do it right.

i did a VE tune in open loop, and it took care of quite a few issues. the table was off. i did have trouble hitting all the spots on there though... i might be dynoing the car saturday, so if i do that im going to see if i can hit those cells while on the dyno.

i am not opposed to the ve helping the maf, thats how it works. i am just opposed to running a full time SD setup. i much prefer the maf.

[joshz06]

car is still doing it... although not as frequent. now, sometimes it returns to idle perfectly, sometimes it hangs at about 1150rpms, and sometimes it drops down to 500. really driving me nuts. its not the ve fueling. i have messed with that more than i care to. its not the maf table. i adjusted those both and it did nothing.