which tables to correct dipping idle on decel?
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
which tables to correct dipping idle on decel? ok so throttle in, coasting to a stop. the rpms come down but dip too low, then recover. i want to stop this. throttle cracker is the airflow the computer wants at a given speed correct? the throttle follower settings have to do with how the throttle is opened and closed and how fast and how slow that it is correct? so if my rpms dip too much, the throttle decay table is reduced that woudl help right? i have messed around with it somewhat but want to know what (if anything) you all did to fix it. yes i have my own effective area table and no thats not the problem. i put the stock one back in the car, redid the RAF and everything else and that didnt do anything for it, made recovery worse.
You need to dial in your effective area first and foremost. Then go do RAF again. At that point it should be pretty solid, but you may want to tweak the cracker table, and yes, you can reduce the decay to help out as well.
When dialing in your effective area, I believe its heavily based off of VE, so if youre VE was not dead on (maybe you have it a little rich for SD mode) the then effective area might not be right and may cause the stalling. Just an idea, if you for your then for anyone else who has a similar prob.
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
yeah i meant clutch in sorry lol. my VE is all done then i did effective area then i did RAF which is why i feel the throttle airflow tables have to do with it. ill try some stuff, thanks
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TECH Enthusiast
Joined: Mar 2004
Posts: 647
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From: Australia
You could also shift cells to the to left in the "Throttle Follower Airflow vs TPS" base table. Stock, there is 0 follower control from 3-5% throttle down. So any follower adjustment will do zip if you take you foot off the pedal completely.
I only use cracker to stop surging and pig-rooting at cruise. When decelerating through the last 2-3km/h its all throttle follower, not cracker.
Hows the idle and the rest of your issues? All sorted now?
I only use cracker to stop surging and pig-rooting at cruise. When decelerating through the last 2-3km/h its all throttle follower, not cracker.
Hows the idle and the rest of your issues? All sorted now?
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
yeah i mixed in some of the sutff you gave me with some other stuff i tried out and its a lot better. im going to put a fresh set of plugs in the car tomorrow. start up is nice now, still kinda odd when its at a slightly cold idle but i think the cold plugs have to do with that (from what i am told).
if im going 35 mph and put the clutch in,the rpms just go right down and then jump up 200 and kinda slowly steady out. would that be the follower? the tables just confuse me on the definition in hp tuners. when you say you use the cracker to stop surging, how do you adjust it to stop it? also if i increase the follower airflow table, will that effect any kind of bucking when i get on the gas from too much air? this is about the last step before i put the computer away and leave it alone haha so i would like to get it straitened out!
if im going 35 mph and put the clutch in,the rpms just go right down and then jump up 200 and kinda slowly steady out. would that be the follower? the tables just confuse me on the definition in hp tuners. when you say you use the cracker to stop surging, how do you adjust it to stop it? also if i increase the follower airflow table, will that effect any kind of bucking when i get on the gas from too much air? this is about the last step before i put the computer away and leave it alone haha so i would like to get it straitened out!
TECH Enthusiast
Joined: Mar 2004
Posts: 647
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From: Australia
Decel. is all follower. Cracker opens the IAC motor on accel. and maintains airflow at cruise. Everything, though, based around the Base Running Airflow table. You always start there - solves 90% of all problems.
If you have zeroed out the first dozen IAC cells in the "IAC vs Effective Area" table then its slewing your follower control, hence dropping right down. Whats recovering for you is the Stall Saver.
I would set the cracker and IAC tables back to stock and work from there.
If you have zeroed out the first dozen IAC cells in the "IAC vs Effective Area" table then its slewing your follower control, hence dropping right down. Whats recovering for you is the Stall Saver.
I would set the cracker and IAC tables back to stock and work from there.
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
i did put the iac and all that back to stock with no help. my car has best results with the effective area table i have in there now. i dont have any stall saver in there, thats one of the things i didnt copy over yet. the more i think about it the more i think that it is related to closed loop fueling. when the fuel trims are not working the car seems to go right to desired rpm without over or undershoot.
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
if it happens to me on decel, when the clutch is in, woudl that be p/n follower settings? that is where i am confused. if its all due to closed loop fueling im not even gonna mess with it anymore
Originally Posted by WS6FirebirdTA00
if it happens to me on decel, when the clutch is in, woudl that be p/n follower settings? that is where i am confused. if its all due to closed loop fueling im not even gonna mess with it anymore
Originally Posted by MNR-0
If you have zeroed out the first dozen IAC cells in the "IAC vs Effective Area" table then its slewing your follower control, hence dropping right down. Whats recovering for you is the Stall Saver.
Throttle follower Decay(gear) and Delay(gear) fixed mine. I delayed how long the decay kicks in, and slowed down Decay. Bumped up my RAF a few percent and its perfect.
I still have a bug in my PCM i'm working on. From time to time it wont want to idle at all in park or drive, and has stalled a few times coming to a stop. the only fix is to turn the car off then back on and its fixed. It'll throw p0506 when the condition occours. Its occoured stock and still shows up sometimes after tuning and mods.
I still have a bug in my PCM i'm working on. From time to time it wont want to idle at all in park or drive, and has stalled a few times coming to a stop. the only fix is to turn the car off then back on and its fixed. It'll throw p0506 when the condition occours. Its occoured stock and still shows up sometimes after tuning and mods.
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
car is fine in open loop, it is all due to fueling. messed with the throttle cracker to get the rpms nice comming to a stop. im sure i could decrease the decay to make it last longer but thats patching a problem that is there. the second i turn off closed loop the **** is perfect, no over or undershoot at all. so ill deal wiht it until i have an open loop tune 
